From the UNIVERSITY OF CALIFORNIA – BERKELEY

*Einstein’s equations allow a non-determinist future inside some black holes*

In the real world, your past uniquely determines your future. If a physicist knows how the universe starts out, she can calculate its future for all time and all space.

But a UC Berkeley mathematician has found some types of black holes in which this law breaks down. If someone were to venture into one of these relatively benign black holes, they could survive, but their past would be obliterated and they could have an infinite number of possible futures.

Such claims have been made in the past, and physicists have invoked “strong cosmic censorship” to explain it away. That is, something catastrophic – typically a horrible death – would prevent observers from actually entering a region of spacetime where their future was not uniquely determined. This principle, first proposed 40 years ago by physicist Roger Penrose, keeps sacrosanct an idea – determinism – key to any physical theory. That is, given the past and present, the physical laws of the universe do not allow more than one possible future.

But, says UC Berkeley postdoctoral fellow Peter Hintz, mathematical calculations show that for some specific types of black holes in a universe like ours, which is expanding at an accelerating rate, it is possible to survive the passage from a deterministic world into a non-deterministic black hole.

What life would be like in a space where the future was unpredictable is unclear. But the finding does not mean that Einstein’s equations of general relativity, which so far perfectly describe the evolution of the cosmos, are wrong, said Hintz, a Clay Research Fellow.

“No physicist is going to travel into a black hole and measure it. This is a math question. But from that point of view, this makes Einstein’s equations mathematically more interesting,” he said. “This is a question one can really only study mathematically, but it has physical, almost philosophical implications, which makes it very cool.”

“This … conclusion corresponds to a severe failure of determinism in general relativity that cannot be taken lightly in view of the importance in modern cosmology” of accelerating expansion, said his colleagues at the University of Lisbon in Portugal, Vitor Cardoso, João Costa and Kyriakos Destounis, and at Utrecht University, Aron Jansen.

As quoted by Physics World, Gary Horowitz of UC Santa Barbara, who was not involved in the research, said that the study provides “the best evidence I know for a violation of strong cosmic censorship in a theory of gravity and electromagnetism.”

Hintz and his colleagues published a paper describing these unusual black holes last month in the journal *Physical Review Letters*.

**Beyond the event horizon**

Black holes are bizarre objects that get their name from the fact that nothing can escape their gravity, not even light. If you venture too close and cross the so-called event horizon, you’ll never escape.

For small black holes, you’d never survive such a close approach anyway. The tidal forces close to the event horizon are enough to spaghettify anything: that is, stretch it until it’s a string of atoms.

But for large black holes, like the supermassive objects at the cores of galaxies like the Milky Way, which weigh tens of millions if not billions of times the mass of a star, crossing the event horizon would be, well, uneventful.

Because it should be possible to survive the transition from our world to the black hole world, physicists and mathematicians have long wondered what that world would look like, and have turned to Einstein’s equations of general relativity to predict the world inside a black hole. These equations work well until an observer reaches the center or singularity, where in theoretical calculations the curvature of spacetime becomes infinite.

Even before reaching the center, however, a black hole explorer – who would never be able to communicate what she found to the outside world – could encounter some weird and deadly milestones. Hintz studies a specific type of black hole – a standard, non-rotating black hole with an electrical charge – and such an object has a so-called Cauchy horizon within the event horizon.

The Cauchy horizon is the spot where determinism breaks down, where the past no longer determines the future. Physicists, including Penrose, have argued that no observer could ever pass through the Cauchy horizon point because they would be annihilated.

As the argument goes, as an observer approaches the horizon, time slows down, since clocks tick slower in a strong gravitational field. As light, gravitational waves and anything else encountering the black hole fall inevitably toward the Cauchy horizon, an observer also falling inward would eventually see all this energy barreling in at the same time. In effect, all the energy the black hole sees over the lifetime of the universe hits the Cauchy horizon at the same time, blasting into oblivion any observer who gets that far.

**You can’t see forever in an expanding universe**

Hintz realized, however, that this may not apply in an expanding universe that is accelerating, such as our own. Because spacetime is being increasingly pulled apart, much of the distant universe will not affect the black hole at all, since that energy can’t travel faster than the speed of light.

In fact, the energy available to fall into the black hole is only that contained within the observable horizon: the volume of the universe that the black hole can expect to see over the course of its existence. For us, for example, the observable horizon is bigger than the 13.8 billion light years we can see into the past, because it includes everything that we will see forever into the future. The accelerating expansion of the universe will prevent us from seeing beyond a horizon of about 46.5 billion light years.

In that scenario, the expansion of the universe counteracts the amplification caused by time dilation inside the black hole, and for certain situations, cancels it entirely. In those cases – specifically, smooth, non-rotating black holes with a large electrical charge, so-called Reissner-Nordström-de Sitter black holes – an observer could survive passing through the Cauchy horizon and into a non-deterministic world.

“There are some exact solutions of Einstein’s equations that are perfectly smooth, with no kinks, no tidal forces going to infinity, where everything is perfectly well behaved up to this Cauchy horizon and beyond,” he said, noting that the passage through the horizon would be painful but brief. “After that, all bets are off; in some cases, such as a Reissner-Nordström-de Sitter black hole, one can avoid the central singularity altogether and live forever in a universe unknown.”

Admittedly, he said, charged black holes are unlikely to exist, since they’d attract oppositely charged matter until they became neutral. However, the mathematical solutions for charged black holes are used as proxies for what would happen inside rotating black holes, which are probably the norm. Hintz argues that smooth, rotating black holes, called Kerr-Newman-de Sitter black holes, would behave the same way.

“That is upsetting, the idea that you could set out with an electrically charged star that undergoes collapse to a black hole, and then Alice travels inside this black hole and if the black hole parameters are sufficiently extremal, it could be that she can just cross the Cauchy horizon, survives that and reaches a region of the universe where knowing the complete initial state of the star, she will not be able to say what is going to happen,” Hintz said. “It is no longer uniquely determined by full knowledge of the initial conditions. That is why it’s very troublesome.”

He discovered these types of black holes by teaming up with Cardoso and his colleagues, who calculated how a black hole rings when struck by gravitational waves, and which of its tones and overtones lasted the longest. In some cases, even the longest surviving frequency decayed fast enough to prevent the amplification from turning the Cauchy horizon into a dead zone.

Hintz’s paper has already sparked other papers, one of which purports to show that most well-behaved black holes will not violate determinism. But Hintz insists that one instance of violation is one too many.

“People had been complacent for some 20 years, since the mid ’90s, that strong cosmological censorship is always verified,” he said. “We challenge that point of view.”

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Mythology.

Sorry, … mathemythology.

What do you call the most blessed ‘Math’? String Theory

There is no string theory per say, If ‘theory’ is defined to be a real model that could be compared to physical phenomena.

The String ‘Theory’ team (1000 people working diligently away for 30 years) have yet to develop with a model. A model is the first step in coming up with a theory.

What the String Team have proven is it does not matter how smart you are, if the direction you are going in requires the changing of the reality of what is mathematics and what is something that might lead to a breakthrough. Madness is doing the same thing over and over and expecting something different.

The String Team should have long ago been asked to identify the direction they are going in and when they are going to give up on whatever task they believe they are doing.

Science gets it power from its connection to the physical world.

William, if they only wouldn’t have fooled themselves by propter nomen. As soon as they discovered the need of more dimensions for their model they would have been able to extend the dimensions of their one-dimensional acting object into say, three dimensions, pulsating spheres. Instead they are limited to 1D and their objects have to act in what – about 11 dimensions?

I wonder why every time Anthony ventures into cosmology, the reaction is this. The black hole maths is very hard, but it is not mythology, just very theoretical. Plain-language explaining seems to almost always fail, there were severel points above that made the lift eyebrows as what is popularized there appears just incorrect or misleading.

I happen to think the censorship will be proven to work in every case. But I have abandoned hope that I’d ever understand the maths. You have to be under 25 to have time to learn it.

Hugs: Please allow me to explain the reaction. Some science I can learn and understand; some science is too hard for me to learn, but I can read and at least grasp a bit. Then there’s theoretical physics and “determinism”. The very idea that the future is “determined” is counterintuitive to life on earth, where the future is anything but determined. In the mind of a physicist, the earth’s future is determined, it will orbit the sun until the sun starts to burn out, expanding until earth is properly cooked. But the future is not determined for me, I can post this or I can cancel it; I can keep reading this or switch to Steynonline to see if Mann’s lawsuit has emerged from the black hole of the DC Court (so I pray that something CAN emerge from a black hole). In my mind, the future is obviously not related to anything theoretical physics puts out. That said, I’m just humble enough to recognize that it is not mythology, and they are thinking on a higher level than ordinary humans like me. And I’ll worry more about being swallowed by a black hole than about CAGW.

“I wonder why every time Anthony ventures into cosmology, the reaction is this.”

I think it’s because of all the circular reasoning, assumptions, and fantasy involved. The “science” people are rhetorically turned into all-knowing gods, and then all manner of totally unproven (and potentially unprovable) things are conjured up out of a few scraps of empirical evidence and some imagination . .

“If a physicist knows how the universe starts out, she can calculate its future for all time and all space.”

No she can’t . . Prove me wrong ; )

Actually determining the future by such means would require infinite knowledge. You would literally need to know the complete status of every particle in the universe down to quantum states, and knowledge of the causal mechanisms behind changes in quantum states, which we can’t know because we can’t observe them in action.

Even if the requisite knowledge was possible, simply calculating the changes even a few milliseconds out for every particle in the universe would take many orders of magnitude more computing power than currently exists on Earth. Count me skeptical that there is enough mass in the universe to build enough computing power to calculate even a few seconds worth of time before the heat death of the universe.

“

I think it’s because of all the circular reasoning, assumptions, and fantasy involved. The “science” people are rhetorically turned into all-knowing gods, and then all manner of totally unproven (and potentially unprovable) things are conjured up out of a few scraps of empirical evidence and some imagination.”Wait – are you talking about cosmology or climate change?

@paul courtney

” In the mind of a physicist, the earth’s future is determined, ”

Actually, no.

This was a XIX century thinking. It broke out, undermined by statistical mechanics, the three-body problem, and utterly broken by experiment leading to quantum mechanics. Einstein said “god does not play dice”, that is, the particle real had a state (“hidden variable”), it just was to hard for us to know it without changing it. And Einstein was proven wrong as certainly as possible (more than 242 standard deviation out of the possibility it randomly happened … THAT is science! not “climate science”) by Bell test experiments

First one has to prove that black holes exist, then you have to prove what they are before any manipulations of esoteric mathematics can be applied. If they exist real maths will be all that is necessary. Our galaxy is expanding, thus a black hole in the middle that sucks things in would seem stupid. Perhaps whatever is in the middle of our galaxy is something that is creating matter, this would seem more logical as we expand to make room for the new stuff?

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Our galaxy is expanding . . . .

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Universe–probably yes; galaxy–probably not.

Jim

Black hole contrarianism is quite what I was talking about. Sure, right, do you have a better idea? What prevents a black hole from being formed?

Much of the critic is pointing at the popular expressions that are not from the original paper…

I was taught that, in science, you may continue your reasoning until you reach a ridiculous/impossible result. At that point, your original idea has been proven incorrect. Mathematics has no such limitation.

It’s amazing what you can conjure up when you divide by zero.

Oh, these days you have to forget about dividing with numbers and use matrices, operators, fiberbundles, and fancy pansy noncommutative algebras. Dividing is so last millennium.

I mean for real, it’s not only complex.

So true. Love the venn diagram!

As Kip Thorne has written, we just do not have good tools to solve Einstein’s equations in general relativity. And getting close to a black hole, to do physical research, kind of limits what information you could send out.

At this point it is still a guessing game.

It reminds me of a remark Feynman made. He was on his way to a program in the Research Triangle and had forgotten to note where the program was. So he asked the guides: “Have you seen some short balding men talking together about g mu nu?” They led him right to the program.

Maybe LIGO will help over time.

Physicists ought to be ashamed of accepting the idea of an event horizon. Having an infinite gravitational force on a particle and infinite time dilation at the horizon ought to make everyone stop and think. Infinities mean that your theory has gone away and left reality behind.

“

Physicists ought to be ashamed of accepting the idea of an event horizon.”But it’s glamorous, government-funded work and brings in the bucks, sort of like another field that has left reality behind.

IYKWIMAITYD

I agree black holes are dead science. Dead science is science that has no connection with the physical world.

Quasars do exist, however, what a quasar is has nothing to do with silly black holes and/or accretion disks.

People in the field have absolutely lost track of the new observations and their implications.

http://arxiv.org/pdf/1512.04434v1.pdf

https://www.sciencedaily.com/releases/2015/12/151216105309.htm

http://www.eso.org/public/news/eso1438/

http://arxiv.org/pdf/1409.6098v1.pdf

@Stan Robertson

Oh please, just do what you suggest, instead of believing others people didn’t.

“infinite” for maths and physics just means “it exist bigger (or smaller, or closer to zero) than you think, whatever you experience”. That’s the very definition.

“infinite” is not a value, it is just the situation when the road never stop, the more you walk toward horizon the more it moves away.

You don’t believe such situation can happen in real world, that those thinking about it have “theory that has gone away and left reality behind.”?

Gravity Wave

The detection of gravity waves has been predicted for 30 years. The detection of gravity waves has nothing to do with the existence of the theoretical entity black hole.

Gravity waves are not new.

We have ‘known’ for 30 years that the orbiting period of binary pulsars decay, slow down, it is assumed by emitting gravity waves according to the calculations within 0.2% of what General Relativity predicts.

https://arxiv.org/pdf/astro-ph/0407149.pdf

There has been no breakthrough in physics, for 30 years.

Dark matter: 40 years looking for evidence. No evidence.

Dark energy: Place holder for theory.

http://physics.princeton.edu/~cosmo/sciam/index.html#facts

Inflation: Name for 100,000 times faster than speed of light expansion that is hypothesized to occur to save the fixed time universe model. After 20 years of theoretical work on Inflation concept it is found if there is good inflation (inflation that occurs only once at beginning of the fixed time universe), then there is also bad inflation which would blow at anytime, in addition to producing conditions which are not observed, See below for a link to the specialists discussion of the issues.

See:

The Trouble With Physics: The Rise of String Theory, The Fall of a Science, and What Comes Next

by Lee Smolin

https://wattsupwiththat.files.wordpress.com/2012/09/davis-and-taylor-wuwt-submission.pdf

What has changed about the inflationary theory? Originally scientists thought that the outcome of inflation (a smooth, flat universe with a certain spectrum of density fluctuations and gravitational waves) was generic. Now we know it is not.

What do you mean? Inflation has two major problems: First of all, we have learned that inflation is highly sensitive to initial conditions. This is the opposite of what everyone thought originally. For example, in the 1990s, by considering different initial conditions and parameters, Linde (and others) championed models of inflation that would lead to an open universe rather than a flat universe, because, at the time, observations seemed to point that way. See, e.g., our Fact Checking section (LINK). We do not hear about these models any more because later measurements showed the universe to be flat.

Second, we have also learned that inflation generically produces a multiverse (“multimess”) of outcomes – literally an infinite number of patches with an infinite diversity of possibilities – and there is currently no criterion to prefer one possibility over another. As Guth has put it, “In an eternally inflating universe, anything that can happen will happen; in fact, it will happen an infinite number of times. Thus, the question of what is possible becomes trivial—anything is possible […] The fraction of universes with any particular property is therefore equal to infinity divided by infinity—a meaningless ratio.” See, highlighted text in the Conclusion section of Guth’s paper published in J.Phys. A40, 2007 (LINK). In other words, there is nothing that says that what we observe in our patch is typical or could be predicted a priori on the basis of the theory.

This is a link to the summary of the problems of Inflation.

http://physics.princeton.edu/~cosmo/sciam/

I wonder if Leif is into all this black hole, neutronium, dark energy, dark matter, etc., etc., ad libitum …

Determinism is not compatible with quantum physics.

Or chaos.

Jim

Determinism is not compatible with quantum physics.

Nor, according to Feynman, with non-quantum physics.

This is not even wrong.

Go and tell Schrödinger’s cat that.

If It isn’t dead.

In fact this view was comprehensively trashed about 1930.

For various reasons no matter how much we know we still can’t predict the future exactly.

I was thinking that since I live in a world with an infinite number of possible futures, we mush have already fallen into the black hole.

made me think of Doug Adams – “There is a theory which states that if ever anyone discovers exactly what the Universe is for and why it is here, it will instantly disappear and be replaced by something even more bizarre and inexplicable.

There is another theory which states that this has already happened.”

Leo, you’re too harsh.

It’s not even right.

It’s a falsifiable claim (which was falsified almost a century ago), not word salad.

Im afraid that Cosmology has succumbed to the disease of computer modelling. Dark energy and dark matter are pink elephants. All the astronomers who believe in those concepts are fools.That leaves 2 sciences that are partially if not totally corrupted, Atmospheric science and Cosmology. What other sciences are in danger of this?. If the authors of the paper had a chance to enter a large black hole Do you think they would have the courage of their conviction?

I say send Al Gore and Nobel Laureate Dr. Michael Mann.

Please, Distinguished Professor Michael Mann.

You mean Distinguisheg Poser Dr. Michael Mann, one of the greatest Charlatan ‘Scientist’ of all time. His name will be synonymous with quackery science, in regards to his contribution to climate science at large. The other guy, Al Gore will just be known as a big loser. And thank goodness for that.

Doesn’t Dr. Mann meet with an unpleasant space demise in

Interstellar?Cosmology now generally accepts the existence of 2 pink elephants 1)Dark energy 2( Dark matter

Therefore all subsequent research in cosmolgy will have to accept these 2 pink elephants or it wont get published. Can you see a frightening parallel to the world of AGW? Any research that has a standard model including those 2 pink elephants is doomed to spew out nonsense and the world of cosmology will be forever corrupted unless these 2 pink elephants are exposed. It may be too late cause how do you disprove a pink elephant?..

Likewise in the field of atmospheric science which is actually the field of AGW, the standard model is founded on voodoo mathematics . The simple equation is Q = @T + R where Q is the heat flux anomaly @ is the coefficient of temperaure forcing, T is the change in temperature and R = the heat flux forcing difference of the amount of solar (Shortwave radiation) absorbed by the earth and the amount of LWIR (longwave infrared radiation) eventually radiated back to space. This equation is nonsense but it is the starting point for all the science behind AGW. The problem with the equation is that Q always has to be set to 0 for equilibrium purposes. No further analysis can be carried out until equilibrium is reached. If you dont have a new equilibrium after a change in temperature then you have chaos which can’t be modeled. The other thing that is wrong is the equation is adding heat with units in degrees K and then multiplying that with @ with units in W/m2*K which then changes the Temperature part to W/m2 once the K cancels out. The last part is the forcing (supposedly from CO2) in units of W/m2 So in the end they end up with 2 parts on the right side of the equation which are in the same units. There are 2 problems with this scenario. The 1st is that they have to have @ as a negative value so that the 2 parts on the right are cancelled out when Q is set to 0 for equilibrium. In their literature they use Lambda but i dont know how to type that symbol so I used @. If Q is not set to 0 you will have a positive heat flux anomaly which is fictitious because then you would be adding temperatures to heat forcing which is ridiculous. So by setting H =0 you are saying that the right side of the equation is in equilibrium. But then @ has to be a negative value for the right side of the equation to also = 0. This alpha has to go more negative as the R goes up so that the 2 terms =0 . So in the end we actaully have a more simplified equation which is @T = -R or R=-@T. You can look at this equation anyway you like by transposing variables but if it is nonsense one way it is also nonsense by multiplying both sides by -1. @ is not a real world variable as it always must be negative because R cannot be negative and the equation can be converted to T = -R/@ to be able to solve for T. T can never be negative if CO2 causes a positive forcing and since R can never be negative, the only remaining term is @ which then must be negative. so they are really saying that as R goes up the Temperature difference goes down which is completely contradictory to the whole theory. The 2nd problem with this standard model is they are directly inferring a direct relationship with Temperature and heat flux forcing. This is not the case if H2O is a negative feedback instead of a positive feedback that they are implying. So they are in fact assuming a positive feedback right from the getgo from their equation 1. The 3rd problem with their scenario is that in some of their papers they argue that in the past H2O has been a cooling effect. So they contradict themselves from paper to paper . How can H2O both be a positive warming effect and a cooling effect at the same time? AGW is all voodoo mathematics.

Alan Tomalty

February 22, 2018 at 10:59 am

You forgot about the 3rd pink elephant…string theory!

As far as I know, no one has ever called for the jailing or execution of people because they do or don’t believe in String Theory.

Not so for AGW.

Incredible — literally — that anyone would make such claims about something that is, to this day, still entirely theoretical. Wild speculation about the theoretical would be a good description.

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Wild speculation about the theoretical would be a good description.

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The observed object, Sagittarius A*, has an estimated mass of 4.1 million solar masses and is smaller than a solar system (based on orbiting stars near it). In fact, it’s estimated to be only about 17 times bigger than the sun. If it’s not a super massive black hole, then what is it?

Jim

@Jim, you’ve got to ask yourself what’s the electrical charge of Sagittarius A, and what’t the electrical charge of its environment. 2 cents of electric universe.

Tend to disagree. Black holes are not theoretical any longer. There are three strong lines of evidence. 1. Only black holes explain the rate of motion of interior objects (star systems) in a galaxy like ours. 2. Energetic gamma ray bursts near galactic centers with no associated supernove evidence almost certainly come from infalling matter approaching the event horizon. 3. We newly have several gravitational wave observations whose characteristics exactly match black hole merger theoretical predictions.

ristvan ==> “strong lines of evidence” — and “whose characteristics exactly match…theoretical predictions” — sounds about as sure as CliSci.

You can like an elegant theory — but that doesn’t move it into the physical universe. Theories about Gravity? Come on, Rud — we don’t even know what gravity really is yet…..only able to measure its effects.

A sci fi it is. Classical physics breaks down at extreme situations – high velocities or low temperatures – about a thousand times beyond our daily experience. The general relativity makes predictions about gravitational fields billions times stronger than that of the Sun – and there are observations confirming predicted effects! Incredible.

@ Kip : “We don’t even know what gravity really is yet…”

That is a poor line of thought. You can say the same about light and magnetism and even matter itself. If science limited itself to only those items which were properly and thoroughly put to bed we would be left with precisely all of nothing.

Explaining what something is comes only by defining the rules it follows and then using those rules to make provable predictions about the future. Relativity and black hole theory predicts a certain behavior in the world. Go here, and look for this. We go out, and we find it. That is as “into the physical universe” as man can delve.

I agree with the idea of a black hole as an object. You don’t have to go further than that to explain the behavior of the surroundings. As to what goes on beyond the event horizon, I am not listening to any speculation like the above , no matter how elegant, until the quantum gravity problem is resolved.

If I understand it, and I very well may not, the existence of black holes is a necessary consequence of the established fact that gravity can bend electromagnetic radiation, purportedly by bending the fabric of space-time. Probably doesn’t matter how gravity and ER interact. They demonstrably do. And therefore sufficient gravity can almost certainly prevent electromagnetic radiation from escaping a sufficiently strong gravitational field.

The fact that black holes can,and almost certainly do exist, does not prove that we understand what is going on within the black hole.

CJ ,

“f science limited itself to only those items which were properly and thoroughly put to bed we would be left with precisely all of nothing.”

First, science is not a self, and second, we would still be left with theories and practical techniques and the like, just not absolute truth/understand . .

Which is where we are, right? ?

Ristvan: “1. Only black holes explain the rate of motion of interior objects (star systems) in a galaxy like ours. ”

Interesting, you do realize that we still cannot explain the motion of entire galaxies or super clusters without fudge factors such as dark matter, do you not? Black holes might exist, I think they are a sexy aspect of space. But again, they certainly are not proven to exist, and using the argument that they are required to explain the motion of star systems is not valid.

Astonerii: “Black holes might exist, I think they are a sexy aspect of space.”

Racism and Sexism. Go stand in a corner.

@ astonerii “using the argument that they are required to explain the motion of star systems is not valid.”

Its not the only leg holding the table, though. The rules of relativity were put together to describe observations of light. The rules predicate certain behavior in certain circumstances. In the extreme gravity situations of super massive stellar bodies the rules predict black holes. This prediction is separate from the observation that such a super massive body is needed to make the galaxy spin as it does. Such a thing is possible within the rules, such a thing is predicted by the rules, such a thing is needed by observations. Stable.

Then the rules go on to show how two black holes merging should behave, and how you could detect that (gravity waves). When technology became sufficiently advanced, we looked and such behavior was found.

This is a different situation altogether from dark matter and dark energy, which are used to explain why the rules do NOT predict the observed universe. Dark Matter for the observation that the apparent mass of the universe doesn’t add up to the gravity seen. Dark Energy for the observation that gravity should draw all matter in to itself, but that the universe is not drawing together or even slowing down, but in fact speeding up and pulling away. Without these ‘fudge factors’ we are left with causeless effect, and that’s usually bad when the name of the game is ‘Predict the Future!”

Melding quantum gravity and relativity may one day, hopefully, yield better answers, but for now this is what we can use to make useful predictions.

Asking what gravity really is, or light, or matter, or space-time, makes me ask what kind of answer you’d expect? What would be a constituent that you’d not go on asking what it is in turn?

Pressured to answer, I’d say everything is logic, and the reason it exists is perhaps that it just is unable to not exist. The world is mathematical behind everything else, to the extent that fundamental physics is eventually nothing but mathematics.

ristvan, The quintessential feature of a black hole is the event horizon; a place where gravitational forces become infinite even though neither mass nor a spacetime curvature singularity can be found there. I don’t know a single competent physicist who admits to believing such a thing exists in nature. The things astronomers think to be black holes are certainly exotic collapsed objects, but we are not lacking for ways to understand them. Numerous papers that describe viable alternative to the black hole model have been published in top flight peer reviewed physics journals. For example, one of mine is in The Astrophysical Journal, 2003, V 596, L203-L206, which is available online at arXiv.org as astro-ph/0310078. Two others are a Nova monograph chapter available as astro-ph/0603746 and 0708.2422. None of your items 1,2 or 3 imply the existence of black holes. Further, there is evidence of structure in the gravitational wave signals that is not compatible with the existence of an event horizon. I love your well informed comments on the broad spectrum of things related to climate science, but you need to elevate your game on physics.

Nearly all of science has been adversely impacted by big government bucks that have allowed relatively small groups of people to control the narrative. Physics is no exception. String theory, dark energy and event horizons survive because it is very difficult to get better ideas published and harder yet to get them out to the public. NASA pushes the black hole paradigm hard because the public loves the exotic and the publicity keeps the money flowing in. Don’t believe everything they print.

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stan robertson

February 28, 2018 at 11:13 am

The quintessential feature of a black hole is the event horizon; a place where gravitational forces become infinite even though neither mass nor a spacetime curvature singularity can be found there.

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No. The quintessential features of a black hole are mass, spin, and charge. As I’ve said elsewhere, the only thing happening at the event horizon is the escape velocity equals the speed-of-light. This has the effect of cutting off communications with points interior to the event horizon. You’re confusing the event horizon with the singularity of the black hole. The two are not the same thing.

Jim

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The quintessential feature of a black hole is the event horizon;

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On second thought, the event horizon is a quintessential feature of a black hole. It’s just not the only property, and it’s still not to be confused with the singularity.

Jim

Black holes are probably gravity events, where electrons are pushed away and the nucleus no longer has the benefit of a spacing mechanism, and collapses due to gravity. China Syndrome writ large. Pulling the universe apart? Of the two options, both to explain the accelerating red shift/expanding universe, pulling apart and pushing outward, which is the most attractive from a physics viewpoint? Think electromagnetic rail gun. The Universe is being pushed outward by anti: magnetic? gravity? what?

“The Universe is being pushed outward by anti: magnetic? gravity? what?”At this level of cosmology, I don’t think we can rule out The Will of Allah.

Read Popper on falsificationism and then Lee Smolin on background independent physics. There is more time than space.

Navel gazing.

Even Hawking recanted his earlier theory of black holes. See https://arxiv.org/abs/1401.5761: “…gravitational collapse produces apparent horizons but no event horizons behind which information is lost.”

My understanding is that as you approach the event horizon, your clock slows down until when you reach the event horizon it stops. At that point, nothing can ever change for you so what can determinism mean for a timeless person? What am I missing here?

I used to think Dick Clark was timeless, but eventually it did catch up to even him.

You are using the wrong reference point. To an observer watching you fall into a black hole your clock would be slowing down. You, as you crossed the event horizon, would notice nothing different (assuming the tidal forces didn’t rip you apart first).

Jim

Yes, I understand that from an outside frame of reference what you say is true, but my understanding is that my clock really IS slowing down but since everything in my frame of reference is slowing down at the same rate everything seems perfectly normal. Until my clock stops. At that point what does determinism mean?

From the reference point of the person falling into the black hole, the rest of the Universe is speeding up

“From the reference point of the person falling into the black hole, the rest of the Universe is speeding up”

That is true but that is only a manifestation of the fact that his clock is running slower that the clocks in the rest of the universe. My question is what happens to him in his frame of reference as his clock slows down to a point infinitely close to or actually reaching zero. Can determinism have any meaning when that happens?

I think you are touching on the essence of relativity. In the reference frame of the person falling into the black hole time is running normally and everything else is running faster. If he could somehow get out of his fall and go back outside the effects of the black hole he will find that the universe he goes back to is much farther along than in time than the amount of time he spent by his clock within the black hole’s influence. In theory, those outside the influence of the black hole will never see him enter it, he will be slowing down so much in their frame of reference that the universe will end before he enters. Vice versa, the universe from the perspective of the person falling into the black hole will speed up faster and faster and ultimately end before he enters the black hole.

“In the reference frame of the person falling into the black hole time is running normally and everything else is running faster.”

Is time running normally for the person falling into the Black Hole or does it only appear to be running normally to him since everything in his frame of reference is experiencing exactly the same decelerating rate of time as he approaches the Black Hole?

“Vice versa, the universe from the perspective of the person falling into the black hole will speed up faster and faster and ultimately end before he enters the black hole.”

If the Universe ends before he enters the Black Hole, does the Black Hole exist after the Universe ends? If so, then that means the Black Hole is no longer part of the Universe and what is Determinism without a Universe? If not, Determinism is moot because neither the Universe nor the Black Hole exist.

>>

Ricdre

February 22, 2018 at 10:42 am

Until my clock stops. At that point what does determinism mean?

<<

Your clock will stop when you reach the singularity. Until then, what does it matter? And after then, what does it matter?

People try to put too much physics into the event horizon. The only thing happening at the event horizon is that the escape velocity is equal to the speed-of-light. This has the effect of cutting off all communication with points interior to the event horizon. Time doesn’t stop until you reach the singularity.

Notice that because clocks slow down in gravity fields, the Universe hasn’t existed long enough for any “true” singularities to form.

A collapsing star will not go “poof” and become a black hole. What you see from outside is a star slowly shrinking and slowly becoming redder and redder, and darker and darker until it goes completely black. If you could peer past the event horizon, you’d see the surface of the star frozen just below the horizon. It’s still collapsing, but its reference clock has slowed down.

Jim

from Jim Masterson: “Your clock will stop when you reach the singularity…. The only thing happening at the event horizon is that the escape velocity is equal to the speed-of-light”. OK, I understand what you are saying. So as you get deeper into the gravity well of the Black Hole, your clock slows down (as it does anytime you get deeper into any gravity well) but even when you reach the point where the acceleration-due-to-gravity is equivalent to the escape velocity of the speed-of-light your clock will continue to tick very slowly until you reach the singularity. I guess my error then is thinking that as you approach a point where acceleration-due-to-gravity approaches the escape velocity of the speed-of-light that would be equivalent to being an object being accelerated near to the speed-of-light and for such an object the speed of its clock ticks would approach zero.

Jim and Ricdre,

Again it is a matter of reference frame. Within the reference frame everything really is normal and only appears different to those outside the reference frame. It works both ways. The description of the clock stopping when you reach the singularity is really the outside universe ending at that time.

I want to say thanks to Tom-In-Florida and Jim Masterson for patiently answering my questions. I love this forum because I always learn so much from the people who post articles and comments here, usually about Weather and Climate but also from the occasional forays into other subjects. Also thanks to Anthony Watts for sponsoring this forum.

“Past” and “future” are not places separated from now.

By definition, the past no longer exists, the future does not yet exist, so all that ever exists, is now.

Except on the internet of course where the past exists forever.

On the internet (and Climate Science); the past is ever changing.

In a kind of way it is a tribute to mathematicians in that any idea no matter how strange (not using crazy please note) can have some kind of calculations/models made to support it, however speculatively. But that doesn’t mean it is true. Our “accelerating “ universe interests me, perhaps merely a local effect in something very much larger than anything we can expect to see. Whatever, at least cosmology never harmed anyone, unlike climate alarmism.

The furthest we can “see” is 13.8 billion light years in all directions, meaning at least 27.6 billion light years in diameter if Earth is at the center. The furthest ‘estimated’/calculated distance is 46.5 billion LY in all directions, meaning 93 billion light years in diameter, assuming Earth as the center point.

Is this an open or closed Universe? Depends on whom you ask.

If I understand this as it’s proposed, your options increase in the nondeterministic black hole and you could go mad deciding what road to take: the dark, tangled path or the one hidden in the mists, or the sunny one heading straight toward the mountains on the distant horizon.

Oh, okay – then time travel is possible.

@sara

“Is this an open or closed Universe? ”

The very concept of “universe” imply unity and loneliness, that is; infinity, that is, open at both end of time and with no border in space.

So you mean “are we in a Universe, or a Multiverse? ”

The fact is, everything hints at openness. No borders, no starting point (the “big bang” is actually an horizon, too, not a popping out of somewhere else), no end point. So far.

An extreme example of uniformitarianism. We have studied and measured physical laws and constants for something like two to three centuries. Based on our observations, cosmologists project events billions of years in the unobserved past and future. As a civil engineering analogy, imagine measuring the slope of a highway over a one meter distance, finding it to be constant, and assuming that it must remain constant over the preceding and subsequent 20,000 kilometers.

Well, inductive reasoning is valid in science, isn’t it?

Unless we have some reason to believe that things change, it make sense to believe they don’t. This is the revolution Galileo made explicit, lifted by the theological view that God (i.e., codex of law of nature, for scientist) is unique and has Immutability.

This view may be wrong, but it alone allows science. You cannot do science if you think that gods (plural) constantly interfere contradictorily, or if you think God changes the rule (as opposed to: make some exception called “miracle”)

The mathematics is beyond my learning, but I’ve wondered, in the standard model of relativity, is space time quantized? I think it is. Simple mathematics suggests that infinity doesn’t actually exist, i.e. 0.999… = 1, and that to me suggests that our perception is limited to our quantized “reality.” Not to mention quantum entanglement, our theoretical speed limit of the speed of light, black holes.

Infinity can’t exist. It’s a purely abstract ideology.

Infinity is a useless number because it can’t be added to, you can’t subtract from it, you can’t multiply with it, or divide from it. It is a static meaningless ideological abstract. Useless for anything but fantastical thinking.

Infinity isn’t a number, that’s a common misconception, so it can’t be a useless number without being one at all. It is a concept of not having a boundary. It’s used in mathematics and at the same time mathematics proves that it doesn’t actually exist, in my opinion.

I make the leap that this suggests everything, the whole of reality, is quantized. That’s why I think mathematics as we observe it breaks down as you approach the “very big” and “very small”.

+1 RWTurner.

infinity, as used in mathematics and physics, is just the situation where there is always bigger/ small/closer to zero, wherever you already are.

For instance, the situation where each given increase in energy give you only ever decreasing increase in speed, as you approach light speed.

You would need infinity energy to effectively reach light speed, which you never will.

But you can still add energy, whatever the amount you already have, and this will still increase your speed, whatever how close to light speed your already are.

Depends on what you mean by a number. Infinities make some good cardinals.

Determinism is already dead, killed by random quantum fluctuations. You don’t need no steenkin’ black hole to kill it.

“

In the real world, your past uniquely determines your future. If a physicist knows how the universe starts out, she can calculate its future for all time and all space.”Absolutely not correct. Deterministic chaos makes such certainty impossible for dynamical material systems (pretty much everything).

For humans, the idea supposes a materialistic predestination of choice, action, and creativity, for which there is zero evidence.

Postdocism

I don’t understand why they say the physics breaks down at the exact center of a black hole — R (radius) = 0, so dividing by that is infinite — meaningless. Isn’t there a limit on the smallest existential length — the Plank Length? If so, the smallest radius wouldn’t be zero, it’d be the Plank Length, so the physics wouldn’t actually break down…. No expert here, just wondering…

Our physics as we believe we understand stops at the Plank Length. It cannot be determined what is less than that.

Could one of those futures include immediate access to next week’s Wall Street Journal?

But the question then becomes, if you did have access to next week’s WSG and made trades and investments based on those outcomes, would the new outcomes which now include your additional entries still be the same?

I’d test it with a small amount on the first pass.

But how do you know if that result is different due to your test being smaller?

This is an interesting article, but it leaves a lot of unanswered questions: why does the Cauchy horizon exists – why is there a region inside a black hole where the past cannot be used to predict the future? How come you can avoid the singularity once inside this region? Why would this region hurt to enter? How could you survive in a place where the past does not predict the future? Also, I think the headline and opening statements are a bit overheated; nothing in the article suggests that one of these special black holes could delete your past – even after crossing the Cauchy horizon, you’d still HAVE a past, it just couldn’t be used to predict your next state. Honestly, the whole article feels a bit overexcited – gushing about all the cool ideas without stopping to explain or investigate any of them.

How could you exist in a place where the past does not predict the future? The fact that you exist at the moment you cross the Cauchy horizon says nothing about a moment later, including about your own existence.

I think we should accept that in order to accept a theory that contradicts something pretty well accepted already is that the Universe is not expanding as proposed. There are multiple problems with the Standard Model and one is the possibility that there are a) more types of matter than regular+dark, b) that the speed of light is not constant, c) that there is a type of matter surrounding all gravitational objects that functions in an ‘ethereal manner’. If (a) is true, it explains why (c) changes (b) depending on the direction the photon is headed (an easily replicated experiment).

Crispin“b) that the speed of light is not constant…” Speed of light is not constant, and measurably different depending on the material it is passing through. In a vacuum, it is fastest (3*108); in glass it is as slow as 2*108.Wow. My superscripts didn’t work. (sigh) 3*10^8, and 2*10^8.

But the photon is in a singularity, so c must be constant everywhere and not just in vacuum. You may think about what may change in s = c t when t varies at constant c.

Funny, I saw another article about black holes today, except the other one was discussing the findings which suggested ultramassive blackholes were more numerous than previously thought.

See here: https://newatlas.com/ultramassive-black-holes/53493/

Of course, my first thought upon seeing the title, “”Ultramassive” black holes may be the biggest ever found – and they’re growing fast,” was that we’ve found yet another thing to blame CO2 for. Sadly (for my humor circuit), no mention of CO2 was found in the article.

rip

Thanks to quantum effects, the future is already “non deterministic”.

THIS statement, “but their past would be obliterated”, is the clincher. It shows there are still some undiscovered laws of physics preventing this from happening.

I wouldn’t mind erasing some portions of my past. Not all of my past, of course. Just some I’d rather forget, but my friends keep reminding me. ;-)

This is not correct:

This is old science, global warming scientists discovered this phenomena years ago and use it to modify the instrumental temperature record, erase the Medieval Warm Period and cause the Little Ice Age to become a minor and local weather artifact.

Error in formatting above, should be

This is not correct:

To be able to determine the future based on the past requires that the physicist knows the position and momentum of each particle with absolute precision, but that is not possible.

In the real world we have the Heisenberg’s uncertainty principle which

states that the more precisely the position of some particle is determined, the less precisely its momentum can be known, and vice versa.

/Jan

Hm, wonder why the lost raw data at CRU came to mind …

That’s simply not true. It’s impossible to know the initial conditions with sufficient precision and the necessary computer would be bigger than the universe.

For similar reasons, we can’t even calculate the weather a week out.

That statement (“If a physicist…”) was believed to be true under Newtonian physics. Quantum physics destroyed it. Newtonian physics is still useful, but one has to be careful of the context it is used in.

I can’t remember who said it – Terry Pratchett? Douglas Adams? – but it bears repeating:

“The main problem of theoretical physics is that we are still attempting to describe the Universe in language developed by one monkey to tell another monkey where the best banana tree was”

Ors similar..

The language developed such that one monkey could appear to be telling another monkey where the best bananas are. In reality, the first monkey could send the second monkey off in the wrong direction and preserve the best bananas for himself. When the second monkey later complains, the first monkey could point out that the second monkey had misunderstood his clear-as-day instructions. How was it the first monkey’s fault if the second monkey couldn’t understand plain English? etc. etc. link

If from my reference frame time stops for you then what does time mean to you from your reference frame looking back at me? For you looking back at me the universe in my reference frame has ended from your point of view. It’s like asking what is outside of the space/time we inhabit? Simple, eternity. As someone above said, just divide by zero.

From either reference frame “time”/”universe” ends at the same time. It is a matter of how each reference frames sees the end. From one reference frame the time outside their frame is moving faster and faster, from the other reference frame the time outside their is moving slower and slower.

Tom,

I thought that is what I said. From the refernce frame outside the bh the time inside the bh has slowed while from inside the bh time outside the bh has gone so fast that the universe has “died” its entropy death, assuming no big crunch or rebounding universe. Thinking about inside the bh is not so different from thinking about outside of the space/tkme we inhabit. And if Hawking radiation exists why can’t it leak outside of our space/time as well. Though, to me the only real variable that exists is time, deterministic or not, it may be the key reality in the quantum world even though it varies with velocity and gravity. Or is gravity the key variable? If we ever figure out what gravity is we may have some answers. One thing for sure is that the present generally accepted model of our universe has some big holes in it, pun intended.

Begging 4 oblivion…

Aben, have you watched Symbols of an Alien Sky, and then the revised series Discourses on an Alien Sky?

How can we know something before we know it? Death? We could do math until hell freezes over and still not know the truth. This reminds me of (no disrespect intended) of Rabbis arguing over how many angels can be on the tip of a needle? If you cannot prove it (like statistics because of an opinion.? We have real world problems that need answers.

Science fiction.

In what department of Nordström can I buy such a black hole?

OT: There were 3 pro-CO2, AGW sceptic boothes at C-PAC today, and 2 AGW believer boothes proposing solutions.

Hintz realized, however, that this may not apply in an expanding universe that is accelerating, such as our own. Because spacetime is being increasingly pulled apart, much of the distant universe will not affect the black hole at all, since that energy can’t travel faster than the speed of light.

So, how do you explain entangled particles. Is this not instantanious action across vast distances?

Do physicist not grok Zeno’s Paradox? As far as the black hole is concerned, you are just a speck of mass. Nothing more.

Evidence is mounting that black holes

arereal. But the title of this article ‘Some black holes erase your past’ make it sound like these ‘special case’ black holes may be the ultimate ‘confessional’.“All your past sins are erased, my son. Go…. and sin no more!”The reason none of this makes sense is because of multideminsionality of our universe. Hyper-space exists.

The M-M double slit interferometer photon/wave duality experiment… it’s simply the result of multiple dimensions peeking through into our 4D space-time.

Same this with entangled pairs of quaantum particles. Einstein’s spooky action at a distance. Hyper dimensionality of our universe. Gravity acts an attractive force (gravitons) in our 4D (x,y, z, and +t) existence, but has a repulsive element on other dimensions. Manifold string theory is a gordian knot. But in a bout 100 years some really bright person will be the next Einstein.

And then we’ll have FTL travel. But really it will just be folding of our space-time, such that travel to the past still will not be possible.

The real question is why are we using taxpayer dollars to support this sort of mathematical onanism?

“No physicist is going to travel into a black hole and measure it. This is a math question. But from that point of view, this makes Einstein’s equations mathematically more interesting,”

Ah yes a math problem. There are other more interesting math problems like: Can hyperintelligent pandimensional beings that look like mice live in a 42-dimensional universe?

They look like this

BTW general relativity breaks down at the singularity so it cannot really properly describe black holes. Quantum effects cannot be ignored. We need a quantum gravity theory. This is non-existent and an active area of research. I have a quantum theory of black hole based on my non-singularity theorem. Since Hawking and Penrose formulated the singularity theorems, it send my draft to Penrose for his review and rebuttal.

And you thought Dr. Sheldon Cooper (The big bang theory) was a nutcase ?

At least Bill Parsons isn’t hiding he is a comedian !

You just need to get a sense of perspective is all.

James Bull

And your future and… oh well, just forget it!

Bell’s simple equation made all the above academic, many years ago!

All space-time is a singularity, the only thing that gives black holes some distinction, is their “mass” ;-)

“How can I tell that the past isn’t a fiction designed to account for the discrepancy between my immediate physical sensations and my state of mind?”

“It is no longer uniquely determined by full knowledge of the initial conditions. That is why it’s very troublesome.”

Nothing new here. The human condition. Only Laplace’s demon could know the position and velocity of every subatomic particle at the big bang event horizon. Anyway, the big bang is just an inside out black hole…

Einstein’s equations allow a non-deterministic future inside some black holes.

————

Problem with this is, that according to Einstein’s equations such constructs as per above,while can be considered as allowed, simply end up to be considered as figments of imagination at the very least, from the most basic point of view…and when considering it further, are even worse, figments of wild fictions.

(as that claim stated, it stands truly as a circular reasoning)

The entirety of the subject, as per this blog post consist only as a clear moaning of the spoiled ones…against the scientific method, in principle.

The scientific method in essential and spirit stands as very determining, clearly deterministic in nature…with all the nullification and falsification determined position, as per the main point of this method…

That is what actually the Einstein’s equations actually do offer and give to scientific method in regard to physics, and in the same time subject the astrophysics and cosmology to…an impossible fence to jump over.

In and as per this kind of context the Einstein’s equations consist only as an upgrade of that fence…as a method to make it better, by “electrifying it”…The fence already was there, strong and very high, prior even to Einstein and his equations…

This:

“E = mc2 is the world’s most famous equation—a mathematical formula with the power to transcend the barriers of language and culture.”

This one equation can not be joked around, can not be bypassed or transcended over…under any circumstances, as it stands very much accommodated by the support of the reality of the very science of physics, as an equation passing the test with flying colors, the test of nullification…and it happens to be very much propagating and upholding the deterministic way of the scientific test and scientific method to the out most possible towards and against any hypothesis out there, to a point that this particular equation even consist as the only one with a proper clear Quantum knob, at some given reference.

This equation is a proof of the scientific method being essentially and in spirit deterministic…

That is what moaned and complained about…

The deterministic way of the scientific method, especially as per the above equation is simple:

“No much care what the hypothesis means or not, but when a line under a hypothesis contemplated or propagated, then the nullification and falsification grounds automatically applied and engaged, regardless of one not providing the raw data, or the algorithms processes of such data, or the possible falsification or nullification grounds of the hypotheses….

it simply automatically the scientific method raises its “ugly” head of determinism to be a proper means of test for such claims… regardless how long it may take or not”

This still missing in climatology, no much of a surprise there, as there not yet any Newtons or Einsteins or Mendeleyevs yet, only hansens, phils and manns…

too poor as for the scientific method requirements up to now…

Scientific method, again consist as predetermining…essentially and in its “spirit”…

I can go on and on with my rumblings with this, even in the case of the Dark matter-Dark energy clause, or the Supernovae and the chain reaction considered there, or the silliness of the accelerated expansion of the universe.

The famous equation above, subjects the claim of the expansion of universe to a default failure if contemplated in the grounds of energy-matter, meaning “no way hosey it could be accelerating, in that energy-matter context, as it, could not even be considered as expanding at all under that clause anyway “…

The very grounds of the moaning and the cry out against the determinism and therefor against the scientific method application in physics.

Please do poke me at this. :)

cheers

Peter Hintz

In general relativity, a black hole singularity means infinite spacetime curvature, infinite density, infinite energy. In mathematical physics, when you see infinities in your equations, that means your solutions are wrong. They are not real physical solutions. In quantum mechanics, physicists got rid of infinities by using a mathematical trick (renormalization) But physicists working on black holes just ignore the problem and pretend they have real physical solutions. The singularity theorems of Hawking and Penrose are math not physics. Stop the fantasy and start doing real physics.

One problem people seem to forget is that time slows down in a gravity well. That means it will take an infinite amount of time for the singularity to actually form. A black hole singularity. a mathematical point for a non-rotating black hole and a ring for a rotating black hole, hasn’t completely formed yet. So if Hawking radiation is true, then a black hole will eventually evaporate. It may take trillions and trillions of years, but it’s still a short time compared to infinity.

So assuming you could survive the trip, as you fall into a black hole and head for the dense center, it should evaporate (disappear) before you reach a singularity.

Jim

The time dilation is for observer outside the black hole. No time dilation for observer inside the black hole, or she cannot detect it in principle. The singularity will form in finite time from the reference frame inside the black hole.

I don’t believe in Hawking radiation. It requires a pair of virtual particles becoming real. One with positive energy outside the black hole and one with negative energy inside the black hole. I say it’s crap. We know that virtual particles disappear within the time allowed by the Uncertainty Principle and a pair of virtual particles are non-locally entangled so the different time frames inside and outside the black hole have no effect on them. They interact instantaneously as if time doesn’t exist.

>>

The time dilation is for observer outside the black hole. No time dilation for observer inside the black hole, or she cannot detect it in principle. The singularity will form in finite time from the reference frame inside the black hole.

<<

She’s still falling. She’s falling in our reference frame (if we could observe her); and she’s still falling in her reference frame. Her “finite” time to the singularity represents an “infinite” time in our reference frame.

>>

I don’t believe in Hawking radiation.

<<

Then you don’t believe that the area of an event horizon represents the entropy of the black hole. It was a problem in Thermodynamics that led Hawking to make his (original) claim that black holes must have a temperature.

Jim

It doesn’t matter that we cannot observe from outside the singularity (assuming it exists) it’s still part of the theory because it is observable from the inside. But the singularity is a failure of general relativity.

“The area of the event horizon represents the entropy of the black hole.” True, because the area is proportional to the cube of the Schwarzchild radius, and the radius is directly proportional to the mass of the black hole, and the mass is proportional to number of particles. Boltzmann formula for entropy:

S = k ln W

Where k is the Boltzmann constant and W is the number of microstates, which is a function of the number of particles. That’s how the relationship is derived.

There’s no temperature in the above formulation of entropy. Why is Hawking talking about temperature? Clausius formula for differential entropy:

dS = cQrev/T

Where Q is heat flow and T is temperature of a cyclical reversible process. Assuming black hole as a cyclical reversible heat engine is a stretch of imagination. There’s no heat flow in black holes unless you further assume Hawking radiation. But that is not part of the entropy theory. It’s an additional assumption that is dubious unlike the well-established Boltzmann and Clausius entropy.

>>

But that is not part of the entropy theory.

<<

You’re being serious? As you said, the Clausius formula for entropy is or .

>>

Assuming black hole as a cyclical reversible heat engine is a stretch of imagination.

<<

The use of reversibility makes the computation easier. For all other non-reversible processes, you use . I simply don’t see how you can say temperature (and heat) is not a part of entropy–it’s how it is defined. The entropy involved in any heat transfer is directly proportional to the inverse of the system temperature.

Jim

>>

There’s no temperature in the above formulation of entropy.

<<

The units of entropy are energy per temperature. In SI units, that would be joules per kelvin. It’s the same units as heat capacity, but heat capacity has a slightly different definition from entropy: .

The W in Boltzmann’s formula has no units, so the units come from Boltzmann’s constant. Those units are energy per temperature or in SI units, joules per kelvin. Thus there is temperature in the Boltzmann formula–has to be.

Jim

Can anyone answer this question? If the Universe is extremely large, almost infinite, and every expanding, what is the Universe expanding into?

jymmn

February 24, 2018 at 3:17 am

If there is a Beauty,

How many could there be, perceptions of it, in accordance with the “eye of the beholder”!

The Universe, and many universes, many perceptions, as per many observation points imagined.

You can imagine it like, one universe per each and every galaxy point of observation.

Please note the difference between the Universe and the universe.

It is the perception, the observation that expands, therefor is like from our point of observation that the universe expands, where the expanding of the universe is not in the proper means of matter- energy , but more like in the “light scanning radius” expanding. (weird yes, like backwards :) )

So from this point of view is not the Universe that expands, but only the size of the bubble view perception of it by our point of observation, according to our observing of it. (like in the “is not the spoon that bends……”)

Imagine it like a bubble of view expanding outwards through the Universal space (at the speed of light), constantly.

So, again, is the universe that expands through time in to the Universe, constantly.

Not sure if this kinda of answer makes it more confusing or not, but just offering it as per my point of view.

Just one other point of view among many. :)

The observable universe is finite, about 46 billion lightyears in radius. We don’t know if there’s a bigger universe beyond. I speculate the universe sits in a 42-dimensional hyperspace. It has to be 42 – the answer to life, the universe and everything :-)

I just wonder if that observable 46 billion light years is something so tiny in something so much larger we cannot even contemplate the the enormity of it. Are we no more than the equivalent of an atom in this larger entity? When we look at all the universe, how violent it can be, how much energy it contains, how sterile it seems. how isolated we are, you have to wonder what the is the purpose of all this immensity. I understand my question is more philosophical than scientific, but I wonder if science has any answers.

Dr. Strangelove

February 24, 2018 at 8:34 pm

The observable universe is finite, about 46 billion lightyears in radius.

—————–

When every thing considered ok, the above, no matter how appealing, it simply consists as a fake position, to contemplate, at this stage, as far as my understanding permits…the “46” as a number happens to be an assessment,, an educated guess, no more no less…, an academic assumption, or an academic guess…an assessment, not really directly supported by observations.

It really does not really matter whether it happens to be 46 or 86, what matters is the principle.

In principle you and me diverge significantly, I do accept and try to accommodate that earth happens to be the center of universe in a relative point of consideration (as per observation), in the context of relativity, When in the other hand your position, as put forward, states that this has to be wrong, as earth, actually happens to be the center of universe in an absolute form and position in that regard.

At this point my next question will have to be in the lines, of ,who actually needs to be put under the condition of a straight jacket!…. and live happy ever after!

cheers

Jim

February 25, 2018 at 2:58 am

I just wonder if that observable 46 billion light years is something so tiny in something so much larger

——————–

Maybe I am wrong, but that 46 thingy, is not really a result of observations, not a direct one, only some result of assumptions and or a further “scientific’ exercise….

The 46 or 47 billion lightyear radius is based on the best fit model for the observed accelerating expansion of the universe.

http://www.astro.ucla.edu/~wright/cosmology_faq.html#DN

Dr. Strangelove

February 26, 2018 at 2:41 am

————-

Thank you Doctor…

cheers

http://www.iflscience.com/physics/physicist-claims-have-proven-mathematically-black-holes-do-not-exist/

I should add that I mention Mersini-Houghton’s work solely to advance debate. I cannot say whether it has any merit, and I can neither confirm nor deny that black holes exist.

The existence of black holes is almost certain and generally accepted by astronomers. The hypotheses that physicists invent about black holes are doubtful. It’s annoying they take Hawking’s speculation as fact. The Hawking radiation requires observational evidence. At face value it’s dubious. It predicts bizarre things like negative energy and virtual particles becoming real. Fantastic claims require fantastic evidence.

So it’s a consensus?