Physicists propose test for loop quantum gravity

Jan 03, 2012 by Lisa Zyga feature
Artist's illustration of loop quantum gravity.

(PhysOrg.com) -- As a quantum theory of gravity, loop quantum gravity could potentially solve one of the biggest problems in physics: reconciling general relativity and quantum mechanics. But like all tentative theories of quantum gravity, loop quantum gravity has never been experimentally tested. Now in a new study, scientists have found that, when black holes evaporate, the radiation they emit could potentially reveal “footprints” of loop quantum gravity, distinct from the usual Hawking radiation that black holes are expected to emit.

In this way, evaporating black holes could enable the first ever experimental test for any theory of quantum gravity. However, the proposed test would not be easy, since scientists have not yet been able to detect any kind of radiation from an evaporating black hole.

The scientists, from institutions in France and the US, have published their study called “Probing Loop Quantum Gravity with Evaporating Black Holes” in a recent issue of Physical Review Letters.

“For decades, Planck-scale physics has been thought to be untestable,” coauthor Aurélien Barrau of the French National Institute of Nuclear and Particle Physics (IN2P3) told PhysOrg.com. “Nowadays, it seems that it might enter the realm of experimental ! This is very exciting, especially in the appealing framework of loop quantum gravity.”

In their study, the scientists have used algorithms to show that primordial black holes are expected to reveal two distinct loop quantum gravity signatures, while larger black holes are expected to reveal one distinct signature. These signatures refer to features in the black hole’s energy spectrum, such as broad peaks at certain energy levels.

Using Monte Carlo simulations, the scientists estimated the circumstances under which they could discriminate the predicted signatures of loop quantum gravity and those of the Hawking radiation that black holes are expected to emit with or without loop quantum gravity. They found that a discrimination is possible as long as there are enough black holes or a relatively small error on the energy reconstruction.

While the scientists have shown that an analysis of black hole evaporation could possibly serve as a probe for loop quantum gravity, they note that one of the biggest challenges will be simply detecting evaporating black holes.

“We should be honest: this detection will be difficult,” Barrau said. “But it is far from being impossible.”

He added that are not the only possible probe of loop quantum gravity, and he’s currently investigating whether loop quantum gravity might have signatures in the universe’s background .

“I am now working on the cosmological side of loop quantum gravity,” Barrau said. “This is the other way to try to test the theory: some specific footprints in the cosmic microwave background might be detected in the future.”

Explore further: MRI for a quantum simulation

More information: A. Barrau, et al. “Probing Loop Quantum Gravity with Evaporating Black Holes.” Physical Review Letters 107, 251301 (2011). DOI: 10.1103/PhysRevLett.107.251301

Journal reference: Physical Review Letters search and more info website

4.3 /5 (41 votes)

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rawa1
1.4 / 5 (21) Jan 03, 2012
Abstract is here. They do want to study the quantum evaporation of microscopic primordial black holes, which were never observed. It's improbable such objects would be observable at cosmological distances. Their spectrum should exhibit distinct spectral lines by LQG in similar way, like spectrum of hydrogen atom. Other models lead to less or more smooth spectrum.

http://arxiv.org/abs/1109.4239

In AWT the only primordial black holes are quite common atom nuclei, which are stable. They cannot evaporate, until they're not radioactive. If they decay, the indeed exhibit some lines in their energy spectrum.
thuber
1.3 / 5 (11) Jan 03, 2012
Researchers are beginning to feel pressure because string theory and its offshoots like LQG remain untestable.
thingumbobesquire
1.8 / 5 (16) Jan 03, 2012
"Evaporating black holes" sounds like an apt metaphor for the economy to me...
Noumenon
3.3 / 5 (103) Jan 03, 2012
Researchers are beginning to feel pressure because string theory and its offshoots like LQG remain untestable.


So far. What is certain is that if it is not testable, it is not science.

conjecture -> hypothesis -> theory
JIMBO
1 / 5 (8) Jan 03, 2012
This is interesting, but shows little to no chance of a viable phenomenology. Hawking radiation has been simulated using lasers, so perhaps this offers a chance at detection ?
Almost unnoticed, is last year's measurement by the INTEGRAL sat of a New scale of quantum gravity, 14 decades below the Planck length. This re-levels the entire playing field of QG.
Noumenon
Jan 03, 2012
This comment has been removed by a moderator.
Skultch
4.6 / 5 (32) Jan 03, 2012
@TheGhostofOtto1923
You rated me a one for the above comment. Why? Or are you a drive by rater.


Dude, give it a rest and grow up already. Why do you care at all? Frankly, I'm kind of annoyed that now I have to ignore all your posts like I do with the Aether and neutron repulsion guys. Your comments weren't childish and worthless like this when I started on this site.

Why could he have given you a 1? I don't know, but maybe it's because you are provoking an epistemology argument for the 10^34th time, and it doesn't add anything to THIS topic. ???? Will that ever get old for you?

Ok. Ok. I'm in a bad mood again. You guys need to start being more entertaining, ASAP! ;P
GreyLensman
4.6 / 5 (20) Jan 03, 2012
@TheGhostofOtto1923
You rated me a one for the above comment. Why? Or are you a drive by rater.

The original comment is poor, your me-too is no improvement.
typicalguy
5 / 5 (10) Jan 03, 2012
Researchers are beginning to feel pressure because string theory and its offshoots like LQG remain untestable.

LQG is a competitor to and not a type of string theory.
Noumenon
Jan 03, 2012
This comment has been removed by a moderator.
Skultch
4.3 / 5 (22) Jan 03, 2012
You're nitpicking at best and still acting like a child. Your off topic crusade is as transparent as the Aether/repulsion crusades. No one cares if this fits your definition of "science," or not. All I'm saying is that people might start caring about your opinions again if you just let it go. I did, and I'm much happier for it.

So, you've got nothing intelligent to say or ask about irt LQG? Well, I might.

What would the evidence be, exactly? Would it be the effect of some different kind of virtual particle (pair?) on the photons that reach our instruments? How? Thanks.
Noumenon
3.3 / 5 (94) Jan 03, 2012
There is only ONE definition of science, which involves the inductive method, and the possible falsification of theories, as stated in my 1st post. This is matter of fact, not of opinion.

I've stated my motivation for engaging in a "off topic crusade", in this thread.. what was yours?
Eoprime
3.4 / 5 (12) Jan 03, 2012
There is only ONE definition of science, which involves the inductive method, and the possible falsification of theories. This is matter of fact, not of opinion.


Read the article (again) and try to understand it, maybe you will find the points you are complaining about
Noumenon
3.5 / 5 (86) Jan 03, 2012
There is only ONE definition of science, which involves the inductive method, and the possible falsification of theories. This is matter of fact, not of opinion.


Read the article (again) and try to understand it, maybe you will find the points you are complaining about


Reread my 1st post, I said, "so far" in response to thuber saying it is not testable, and further, "IF", "it is not testable", than it's not science.

What specifically was I "complaining" about, Frank (or VD)
Skultch
4.3 / 5 (17) Jan 03, 2012
It's a total waste of time to bring up the idea that this may or may not YET be inductive science. (It's also childish to complain about ratings.) Bringing up the observation/induction point is pointless (covered in the article well enough) and it damages your credibility in that it's irrelevant and can only influence people to expect that your future posts will also be pointless. Will it add to the understanding of reality? If yes, then let's please...just....move....on already.
Noumenon
3.4 / 5 (92) Jan 03, 2012
It's a total waste of time to bring up the idea that this may or may not YET be inductive science. Bringing it up damages your credibility in that it's irrelevant and can only influence people to expect that your future posts will also be pointless. Will it add to the understanding of reality? If yes, then let's please...just....move....on already.


None of YOUR posts above are relevant to the topic as hand, so stop being a hypocrite.

On the other hand IT IS relevant to certain theories that they be testable to bring them within the realm of science. This is a known issue with string or m-theory for example.

If you had reading comprehension skills you would have seen that I was responding to thuber saying is it NOT a science by me saying "SO FAR".

So far everyone of your posts towards me have been childish and irrelevant to the topic, and much worse than complain about 1-raters. I was trying to engage GhostOtto into a substantive discussion, rather than rate contest.
Skultch
4.6 / 5 (11) Jan 03, 2012
Thuber's post was all that was needed. You're right. The rest, including mine, were off topic. Yet, you feel the need to keep restating multiple obvious things. I actually submitted an on-topic question. You?
Noumenon
3.4 / 5 (91) Jan 03, 2012
Ok then, I'll submit an on-topic question with the same quality and haste as yours,.... Is loop quantum gravity shiny?

Thuber's post was all that was needed.


No it wasn't, ...it required a "SO FAR" comment.
GSwift7
4.3 / 5 (18) Jan 03, 2012
Ok. Ok. I'm in a bad mood again. You guys need to start being more entertaining, ASAP! ;P


when I don't give any rank at all, just assume it's a zero, which is worse than a one. lol.

To Noumenon:

I'm willing to accept your proposal that science must be testable. However, as with General Relativity, just because it wasn't testable at that time, it doesn't mean that it is not testable. The competing theories for quantum gravity are all testable, we just lack the technology to do so. So, I agree that science should be testable, but I disagree when you say that the above isn't testable. The very subject of the story is that they think they know a way to test it. There are other tests as well, but this test is unique because they claim their new test can differentiate between different theories. Other tests leave the answer open to multiple choices, though some old theories (eather for example) have been eliminated.
Callippo
1.2 / 5 (22) Jan 03, 2012
Will it add to the understanding of reality? If yes, then let's please...just....move....on already.
Why to ignore the AWT, after then? Mainstream physics is typical with it's obstinate search for phenomena and artifacts, which are known for many years already. For example:

Microblack holes = atom nuclei
Gravitational waves = CMBR noise
Cosmic strings = fibers of dark matter
Antimatter = dark matter
Tachyons = CMBR noise
Photinos (SUSY thingies) = neutrinos
Extradimensions, parallel Universes = everything around us

GSwift7
4.1 / 5 (8) Jan 03, 2012
One key thing to note about Monte Carlo method is that you can't guarantee that you are getting the right result. You can estimate your chance of being correct, but if there are multiple choices of correct answers and they have similar Monte Carlo distributions, then you can't know which choice is being described by the simulation with certainty. For example, on the Wiki page for Monte Carlo Simulation, they show an animated example of using Monte Carlo to find Pi. If you were using Monte Carlo to figure out whether the shape was a circle or an elipse, you might get the wrong answer if the elipse is not very flat. You would need many, many samples to check for an exact fit before you could be reasonably sure of your answer. Even then, you would need to have a prety good idea of the pattern you are looking for in advance. I'm not sure any quantum gravity theory is advanced enough to allow Monte Carlo analysis like this. Too many unknown degrees of freedom in all cases.
pauljpease
4.7 / 5 (11) Jan 03, 2012


B) I never invoked an epistemology argument above; I invoked inductive method which is the foundation of science, based on OBSERVATION.


Perhaps you mean "deductive" rather than "inductive"? Induction surely cannot be the foundation of science. Have you ever heard of the problem of induction? And by the way, if you are asserting the kind of knowledge (e.g. inductive) then it is an epistemological argument, epistemology being the study of the nature of knowledge itself.

But that's ok, once you accept that absolutely nothing that is posted here has any relevance outside of the few people who read these comments then you can just sit back and try to squeeze a few moments of entertainment out of it.
vega12
4.8 / 5 (18) Jan 03, 2012
Why to ignore the AWT, after then? Mainstream physics is typical with it's obstinate search for phenomena and artifacts, which are known for many years already. For example:

Microblack holes = atom nuclei
Gravitational waves = CMBR noise
Cosmic strings = fibers of dark matter
Antimatter = dark matter
Tachyons = CMBR noise
Photinos (SUSY thingies) = neutrinos
Extradimensions, parallel Universes = everything around us



You and your off shoot personality rawa1 are essentially equivalent to a spam bot created by the person who came up with the idea of AWT. Show a little personality, or else it will be exceedingly clear that your only purpose on the internet is the recruiting of new believers into your belief system. Analogies do not a theory make, no matter how appealing they may be to you.
FrankHerbert
2.8 / 5 (24) Jan 03, 2012
What an interesting article!

It seems, sadly, that the anti-science bawl babies on this site, ONCE AGAIN, have not read the article.

So far. What is certain is that if it is not testable, it is not science.

conjecture -> hypothesis -> theory


Did you read the article Noumenon? They specifically propose a test for LQG. You're too busy with your little disinformation campaigns to notice though, aren't you?
Noumenon
3.4 / 5 (87) Jan 03, 2012
Perhaps you mean "deductive" rather than "inductive"? Induction surely cannot be the foundation of science. - pauljpease


No, I mean inductive,... (empirical observation is fundamental to science).

http://wik.ed.uiu..._methods

Deductive reasoning is certain knowledge but one cannot learn anything new, not already contained in the axioms, about reality from it alone.

Inductive reasoning is uncertain, or at best based on probability, but one can learn new things about reality. i.e. ""No amount of experimentation can ever prove me right; a single experiment can prove me wrong." - Einstein
Noumenon
3.3 / 5 (91) Jan 03, 2012
What an interesting article!

It seems, sadly, that the anti-science bawl babies on this site, ONCE AGAIN, have not read the article.

So far. What is certain is that if it is not testable, it is not science.

conjecture -> hypothesis -> theory


Did you read the article Noumenon? They specifically propose a test for LQG. You're too busy with your little disinformation campaigns to notice though, aren't you?


Yes, that's why when thuber said it is NOT testable, I said "SO FAR" and then said IF, IF it is not testable it is not a science.

If the above turns out to be testable than it is a science. A test was PROPOSED, not carried out successfully, yet, so it is still up in the air,... thus my use of "IF".

You have reading comprehension problems. I know your purpose it trolling, so move along.
Noumenon
3.4 / 5 (87) Jan 03, 2012
if you are asserting the kind of knowledge (e.g. inductive) then it is an epistemological argument, epistemology being the study of the nature of knowledge itself.


Yes, i'm aware. In fact Skultch's complaint is that I bring up epistemology (and Immanuel Kant) too much on this site, like in the thread below. To me this is an odd complaint since as you correctly pointed out, "epistemology being the study of the nature of knowledge itself", and obviously science purports to acquire knowledge.

I just didn't want to feed his misapprehension by using that term here.

http://www.physor...ard.html
Noumenon
3.4 / 5 (88) Jan 03, 2012
I'm willing to accept your proposal that science must be testable. However, as with General Relativity, just because it wasn't testable at that time, it doesn't mean that it is not testable. The competing theories for quantum gravity are all testable, we just lack the technology to do so. So, I agree that science should be testable, but I disagree when you say that the above isn't testable. - GSwift


I agree 100%, but I never said that loop quantum gravity will never be able to be tested.

I said "IF" it isn't testable, than it's not science. In fact in response to thuber saying it isn't testable, I said "SO FAR",.. for the reason you sited.
jsdarkdestruction
3.4 / 5 (5) Jan 03, 2012
i was really hoping for a method that we could employ in the near future. imo it looks like we will be waiting for quite a while before we can test this.
StillWind
1.9 / 5 (18) Jan 03, 2012
How sad. This is what passes for science today. Just as man made Gloabl Warming (AGW) can only be shown by mathematical equations, and not by observed phenomena. We have whole areas of theoretical science sucking up funding for nothing but fantasy. Real science is observing pheneomena, and collecting data. If somethingt can't be observed, and no data collected, then it is not science. Time to pull the plug on these con men.
Skultch
4 / 5 (5) Jan 03, 2012
In fact Skultch's complaint is that I bring up epistemology (and Immanuel Kant) too much on this site, like in the thread below. To me this is an odd complaint since as you correctly pointed out, "epistemology being the study of the nature of knowledge itself", and obviously science purports to acquire knowledge.


I get the whole defining and defending of science. I do it too, and I appreciate that it is done on this site, due to all the cranks with obvious science-bashing agendas. I just don't think it was called for this time. That's all. Sorry if I had a little sand in the vag this time. It happens. :)

Actually, this attitude by me is 100% projection. Noumenon, I have recently gone overboard on my real friends defending science way too vigorously, and am currently trying to reign that behavior in. Time and time again, when I find something annoying and comment on it, it's self-projection. I used to fight with Marjon because he talks like my father. Now I don't care
Parsec
3.7 / 5 (6) Jan 03, 2012
Researchers are beginning to feel pressure because string theory and its offshoots like LQG remain untestable.


So far. What is certain is that if it is not testable, it is not science.

conjecture -> hypothesis -> theory

Simply because a conjecture is not testable today doesn't mean it will never be. This article is a case in point. No one EVER imagined it would be possible to perform experiments that explored at the Plank scale. Yet here is an approach that simply requires somewhat better instruments than we currently possess. So don't write off ideas just because you can';t think of a way of testing them. It is incredibly shortsighted.
Noumenon
3.7 / 5 (78) Jan 03, 2012
@Parsec, yes, again, I didn't mean to suggest that loop quantum gravity, in principal can NEVER be tested,... I wouldn't even say that about string theory. Given the number of posters drawing that conclusion, I must not have been clear. I qualified thubers post by saying "SO FAR",.. so I don't understand where this misapprehension is coming from.

@Skultch, I gave you a five. You may be right, perhaps I didn't need to mention it at all. Honestly, I thought I was qualifying thuber's statement. I'm not "against" any theory or idea, as long as it can in theory meet the requirements of science. On that point, I agree with GSwift7.
Returners
2.2 / 5 (10) Jan 03, 2012
Ok, Hawking Radiation is something which, even if it does occur, should only be occuring in insanely small quantities over extremely long time scales. After all, black holes allegedly require trillions of years to evaporate, so you're talking about an amount of Hawking radiation equaling to maybe 1 gram mass equivalent worth of photons per black hole per year.

Considering the surface of a sphere projected outwards into space in all directions, almost none of the Hawking Radiation from any one black hole would be directed at Earth, maybe as little as just a few photons worth per hour or per day.

This experiment would quite literally looking for a "few" photons at a time over inter-stellar distances, and of course seperating those photons out from the "noise" of all the normal stellar and cosmic activity to determine which, if any of them are from Hawking Radiation.

Best bet: Many, Many, arrays of space-based detectors.
ED__269_
3.7 / 5 (3) Jan 03, 2012
I find a problem with assumptions that lead to expectations of detectable differences. SO!

it might just be me, but if you're interested, reread page 3, and see if you agree with the underlying assumptions?

bare in mind I don't have access to the referenced papers, that support the papers position.

Papers should give a synopsis of the intrinsic dependent assumptions of referenced materials; don't you think? Especially when the entire paper depends on them.
MorituriMax
3.3 / 5 (12) Jan 03, 2012
Noumenon, I gave you a blanket 1 for being a whiner who just won't. let. it. go.

Callippo, rawa, 1s for posting under different aliases.
Vendicar_Decarian
1.1 / 5 (45) Jan 03, 2012
"Hawking radiation has been simulated using lasers, so perhaps this offers a chance at detection ?" - Jimbo

Well, that tells you the math is largely right.

Says nothing about black holes though until you manage to find one.
Vendicar_Decarian
0.8 / 5 (42) Jan 03, 2012
"Ok, Hawking Radiation is something which, even if it does occur, should only be occuring in insanely small quantities over extremely long time scales. " - Ret

The smaller the mass of the BH the larger the curvature of space at it's event horizon and hence the higher the production of radiation from that region.

Presuming BH's exist of course.
Vendicar_Decarian
0.7 / 5 (40) Jan 03, 2012
"Just as man made Gloabl Warming (AGW) can only be shown by mathematical equations" - StillTard

http://www.youtub...qgdvXTxE
Telekinetic
1.8 / 5 (20) Jan 03, 2012
Noumenon, I gave you a blanket 1 for being a whiner who just won't. let. it. go.
Callippo, rawa, 1s for posting under different aliases.


Who do think you are, a school teacher? Who cares what you do? Callippo knows about a thousand times more about this subject than you and you know it.
Pete1983
1 / 5 (1) Jan 04, 2012
"Just as man made Gloabl Warming (AGW) can only be shown by mathematical equations" - StillTard

Not to mention that having some mathematics to back up ones assertion is often considered a "good" thing. Amazing comment by StillTard.
Eoprime
4.2 / 5 (5) Jan 04, 2012
There is only ONE definition of science, which involves the inductive method, and the possible falsification of theories. This is matter of fact, not of opinion.


Reread my 1st post, I said, "so far" in response to thuber saying it is not testable, and further, "IF", "it is not testable", than it's not science.

What specifically was I "complaining" about, Frank (or VD)


Not everything can be tested right of the moment you found the theoreticle way to do it. This IS science. That was my point. btw iam not VD FH or someone else. Not like you i got only one account :) i dont need to rate my own posts.

edit:format

TheGhostofOtto1923
3 / 5 (20) Jan 04, 2012
@TheGhostofOtto1923
You rated me a one for the above comment. Why? Or are you a drive by rater
Sometimes. Arguing with you is like arguing with the tv. But lets see here... Nou says
What is certain is that if it is not testable, it is not science
-Which exhibits your fundamental lack of appreciation of how science is done. This is caused no doubt by your affection for philosophy whose practitioners teach that the world can be understood solely by thinking about it.

Too simplistic you say? I say naw. Boil the discipline in a big vat, rend all the fat, skim off all the impurities, scoop out the bones, and this is exactly what you are left with.
http://www.sugarl...duck-fat

-Science is the entire process of
conjecture -> hypothesis -> theory
What is often not testable in conjecture becomes testable in hypothesis. But conjecture is just as much science as hypothesis is.

Many theorists are engaged in conjecture at this moment. They are doing science.
TheGhostofOtto1923
2.9 / 5 (21) Jan 04, 2012
And I see Eoprime and parsec saying much the same thing.
I said "IF" it isn't testable, than it's not science. In fact in response to thuber saying it isn't testable, I said "SO FAR",.. for the reason you sited.
-And youre still juggling words as if theyre actually useful for much of anything. Certainly not for doing science or understanding the world, thats for sure.
Noumenon
3.7 / 5 (76) Jan 04, 2012
What is certain is that if it is not testable, it is not science - Noumenon

-Which exhibits your fundamental lack of appreciation of how science is done. This is caused no doubt by your affection for philosophy whose practitioners teach that the world can be understood solely by thinking about it.


Astonishing. You just accused philosophy of saying the "world could be understood solely by thinking about it", while at the same time expressing some issue with me for saying science requires observation. !!! Patently irrational response from you.

If a physical theory could never be tested by observation, then it would be equivalent what you just accused philosophy of being!

The scientific method is inductive. Yes, you can say for example, that string theorist are "doing science",... but ultimately to quality as a scientific theory, it must be testable. QED
TheGhostofOtto1923
3 / 5 (20) Jan 04, 2012
Astonishing. You just accused philosophy of saying the "world could be understood solely by thinking about it", while at the same time expressing some issue with me for saying science requires observation. !!!
Were you talking scientifically or philosophically when you said this though? Do you know the difference?

You contend that some great philos provided the basis for much of science today. I say that when those philos were contributing to science they were doing science and NOT philosophy. At that point they were no longer philos but scientists.

Some scientists like to dabble in philosophy, like dyson. But when they do so they are not doing science. Many realize this and, like einstein, abandon the effort when they see it is not producing useful results.

Here is the difference between science and philosophy:
Science - loop quantum gravity
Philosophy - ding an sich, dasein, platos forms... und so weiter.
TheGhostofOtto1923
2.8 / 5 (20) Jan 04, 2012
If a physical theory could never be tested by observation, then it would be equivalent what you just accused philosophy of being!
See again you missed the point.

"For a hypothesis to be put forward as a scientific hypothesis, the scientific method requires that one can test it."

Contrasted with:
"A conjecture is a proposition that is unproven but is thought to be true and has not been disproven. Karl Popper pioneered the use of the term "conjecture" in scientific philosophy."

-Of course popper was doing science not philosophy when he did this. Lets check out 'scientific philosophy'...

Oh the link shunts us to this crap:

"Experimental philosophy is an emerging field of philosophical inquiry that makes use of empirical data- often gathered through surveys which probe the intuitions of ordinary people- in order to inform research on philosophical questions."

-So after scientists have had such spectacular success with experimentation, the philos thought theyd give it a try? Ha!
TheGhostofOtto1923
2.8 / 5 (20) Jan 04, 2012
One wonders just who is conducting this data-gathering and whether they are adequately skilled and trained to gather such data in the way scientists would.

The wiki article describes the various topics they are 'exploring'- Consciousness, Cultural diversity, Determinism and moral responsibility, ePIStemology, intentional action, and such. Scientists of various disciplines know there are scientific bases (basises? Basii?) for all these subjects, and their proper understanding can only be determined through scientific inquiry.

Why we do things as individuals and groups for instance can only be explained by exploring the evolutionary nature of the brain, something philos are simply incapable of doing. The best they can do is wait outside laboratory doors so to speak and try to say something cogent about what the boffins are finding out inside.

But then the boffins will come back the next day and, with a little further RESEARCH, prove the philos lacking.
cont
TheGhostofOtto1923
3 / 5 (20) Jan 04, 2012
And consciousness. The more scientists learn about 'consciousness' the more skeptical they become about it being a legitimate 'thing' and not just another useless philo/religious concept from the 19th century. You know, a thing like the soul which can outlive our corporeal containers in some fashion. Philos find refuge and power in these Wunchtraumen in exactly the same way as preachers and priests.

Perhaps I digressed a little? Who knows? No more so than a your typical philo when theyre trying to lay claim to such things as knowledge (ePIStomology), science, morality, etc.
TheGhostofOtto1923
2.8 / 5 (20) Jan 04, 2012
See, this is what happens every time I attempt to do even a little research on philosophy. I find myself having to go back and get my hip boots and muck shovel.
TheGhostofOtto1923
2.9 / 5 (19) Jan 04, 2012
My my thrashy you are a dedicated little lurker arent you? Talk about driveby raters- hey nou, you know this guy? You 2 ever meet on the astral plane perhaps? Some philo encounter group in the big sur?
Dr_Mabuse
4 / 5 (4) Jan 04, 2012
Here is the download adress of the preprint:
http://arxiv.org/pdf/1109.4239
Hope this helps.
AmritSorli
1.6 / 5 (7) Jan 05, 2012
Gravity is a result of diminished energy density of quantum vacuum caused by the presence of mass. In black hole mass is transforming into energy of quantum vacuum......
http://www.spacel...m-vacuum
Blaspheyou
5 / 5 (3) Jan 05, 2012
Physics articles are so much fun to skim. I have no idea what they mean, but it's exciting to see the big words.
TabulaMentis
1 / 5 (4) Jan 05, 2012
The illustration of Loop Quantum Gravity looks something like a cow ball.
Callippo
1 / 5 (8) Jan 06, 2012
Physics articles are so much fun to skim. I have no idea what they mean, but it's exciting to see the big words.
This is how every religion is working, too. People are hardwired so - they're willing to follow big words, until some respected group of people are following them too.
Seeker2
1.8 / 5 (5) Jan 07, 2012
I'm willing to accept your proposal that science must be testable.
I presume this includes plausible.
Seeker2
1.7 / 5 (6) Jan 07, 2012
How sad. This is what passes for science today. Just as man made Gloabl Warming (AGW) can only be shown by mathematical equations, and not by observed phenomena. We have whole areas of theoretical science sucking up funding for nothing but fantasy. Real science is observing pheneomena, and collecting data. If somethingt can't be observed, and no data collected, then it is not science. Time to pull the plug on these con men.

So if we can't observe AGW why worry about it?
Seeker2
1.7 / 5 (6) Jan 07, 2012
http://www.youtube.com/user/greenman3610#p/a/u/0/IQHqgdvXTxE
Good site. But feelgood science, like feelgood religion, has no tolerance for inconvenient truths.
Seeker2
1.9 / 5 (9) Jan 07, 2012
Many theorists are engaged in conjecture at this moment. They are doing science.
Give that man a 5.
Seeker2
1.7 / 5 (6) Jan 07, 2012
Gravity is a result of diminished energy density of quantum vacuum caused by the presence of mass. In black hole mass is transforming into energy of quantum vacuum......
http://www.spacel...m-vacuum

Bad link unfortunately. But I've been beating this drum for who knows how long. I thought I was a lone wolf crying in the wilderness. But I hate the term quantum vacuum - it seems counter-intuitive. I like the term spacetime. Anyway since gravity is a diminished form of this spacetime matter must be an excess of this. Actually I think it is less ambiguous to say matter is an increased energy density of spacetime. So the closer you come to an object the less the energy density of the surrounding spacetime. It seems the U is primarily a matter of spacetime configuration. Or re-configuration. Strange.
Callippo
2 / 5 (4) Jan 07, 2012
It doesn't matter, what you think the vacuum is or isn't, what you like or what you hate, what is strange for you and what not - it's not testable and it's OT.
Seeker2
1.7 / 5 (6) Jan 07, 2012
The illustration of Loop Quantum Gravity looks something like a cow ball.
I'd give this one a 5 if I could.
Seeker2
1.7 / 5 (6) Jan 07, 2012
It doesn't matter, what you think the vacuum is or isn't, what you like or what you hate, what is strange for you and what not - it's not testable and it's OT.
So gravity is not testable. And not applicable to testing LQG. Wait a minute. Isn't gravity included in LQG? And you say it's OT? Wow. Anyway since you don't like my opinions apparently someone else agrees. Sounds like we're making progress.
Callippo
2.3 / 5 (3) Jan 07, 2012
So gravity is not testable.
Nope, your feelings about it are not testable. This is a difference. And your opinions about my feelings are OT here too.
Seeker2
1.7 / 5 (6) Jan 07, 2012
So gravity is not testable.
Nope, your feelings about it are not testable. This is a difference. And your opinions about my feelings are OT here too.
I can feel it sitting right here in my chair. How about you?
Ethelred
2 / 5 (4) Jan 10, 2012
Gravity is a result of diminished energy density of quantum vacuum caused by the presence of mass
Do you have any evidence for ANY energy density for a vacuum and if so do you have any evidence that it is effected by gravity?

I have yet to see any such evidence myself. Of course you don't believe in time so maybe you are using evidence that has only been seen by your future self.

perspective mass is a polarized energy of quantum vacuum which is build up from
positive and negative charged particles.
This does not follow from anything that preceded. And that which preceded was dubious as well. Nor does it fit a universe that has neutral particles and we live sort of universe.

So how about a theory that covers a universe with neutral particles?

I think that enough of that link. A bad start isn't going anywhere.

However Zephir should like it as it has gravity pushing instead of being a curvature of space. Push gravity simply doesn't work.

Ethelred
Seeker2
1.8 / 5 (5) Jan 10, 2012
Do you have any evidence for ANY energy density for a vacuum
I've heard something about a zero point energy. Also something about pair production.

if so do you have any evidence that it is effected by gravity?
Probably not the zero point energy. But strangely enough pair production might not occur as easily without gravity and antigravity working to separate the pair before they annihilate.
Seeker2
1.8 / 5 (5) Jan 10, 2012
perspective mass is a polarized energy of quantum vacuum which is build up from positive and negative charged particles
Strange I can't find that post anywhere. Does sound very creative though.
Seeker2
1.8 / 5 (5) Jan 10, 2012
Do you have any evidence for ANY energy density for a vacuum
I've heard something about a zero point energy. Also something about pair production.

if so do you have any evidence that it is effected by gravity?
Probably not the zero point energy. But strangely enough pair production might not occur as easily without gravity and antigravity working to separate the pair before they annihilate.
BTW check out http://www.physor...ark.html
Ethelred
3.7 / 5 (3) Jan 10, 2012
I've heard something about a zero point energy. Also something about pair production
The total energy remains zero as does the charge. Zero point energy is the MINIMUM energy level so no one can do diddly with it. According to early work on QM the energy level should have been so high that the Universe would not be even remotely flat. The Universe appears to be VERY flat, so flat the zero point energy level must be nearly if not exactly zero. Zero fits the evidence.

Strange I can't find that post anywhere. Does sound very creative though
Its from his link. Amrit has rather 'spiritual' way of looking at things. His science tends toward being pure crap as a consequence.

But strangely enough pair production might not occur as easily without gravity and antigravity working to separate the pair before they annihilate
If only there was any sign of anti-gravity that might be true. Virtual particles do annihilate in nearly all instances in very tiny fractions of a second.>>
Ethelred
4 / 5 (4) Jan 10, 2012
BTW check out
I see no reason to think that anti-matter produces anti-gravity. Positive energy produces gravity and anti-matter has the same positive energy that matter has. Otherwise collisions of matter with anti-matter would not go BOOM.

I would like an experiment to test this of course as logic can often produce more than one result. However the logic I am using seems very solid to me. I have yet to see an equally solid counter argument.

Ethelred
rawa1
1 / 5 (4) Jan 11, 2012
Show a little personality
It's evident, the people who are doing a social club from PO discussion cannot understand, for technical discussion about scientific ideas the person of author is completely irrelevant. Your post just illustrates clearly, the people like you cannot think about these things without explicit name calling.

The situation with contemporary physics is all based about misunderstanding of space-time concept. All people here are talking about it, but no one understands, what it really is. In AWT this thing is modelled with water surface. After then such thing can be described from perspective of longitudinal (quantum mechanics) and transverse waves (general relativity). The first model considers, the water surface is dense environment, through with the waves are emerging at the water surface in indeterministic way. The later one considers the water surface as a thin massless membrane, (the motion of) which doesn't interfere with underwater at all.
rawa1
1 / 5 (4) Jan 11, 2012
Now we have an apparent problem, how to reconcile these two views and derive the TOE, i.e. the general theory of water surface? If you cannot manage it at the case of trivial easy to understand 2D water surface, then I can guarantee you, you cannot succeed with it even at the case of real 4D spacetime. Simply because you don't understand the problem at its fundamental, physical level.
Seeker2
1.8 / 5 (5) Jan 11, 2012
If only there was any sign of anti-gravity...
Normally you would have to chase after it to find it. But some is trapped in the inner Van-Allen belts. Anyway it knows how to give us the slips.
Seeker2
1.8 / 5 (5) Jan 11, 2012
Positive energy produces gravity and anti-matter has the same positive energy that matter has
It certainly does. But gravity is caused by matter having a higher energy density than spacetime. Therefore it sinks into spacetime, searching for the bottom of the pool, until it ends up in a black hole. Anti-matter has less energy density than spacetime, therefore it floats away until it finds a neighborhood with similar energy density. When spacetime expands until it has less energy density than anti-matter, anti-matter will also experience gravity and sink into black holes.
Seeker2
2 / 5 (4) Jan 11, 2012
According to early work on QM the energy level should have been so high that the Universe would not be even remotely flat.
Really. Or did you just make that up? Anyway I hope they got that QM stuff straightened out.
Seeker2
2 / 5 (4) Jan 11, 2012
logic can often produce more than one result.
Really. Where do you come up with this stuff?
Seeker2
1.8 / 5 (5) Jan 11, 2012
it sinks into spacetime, searching for the bottom of the pool
Sometimes it just goes around in circles looking for the bottom of the pool. And then circles go around in even bigger circles, or orbits. But I guess we'll get there eventually.
Seeker2
1.7 / 5 (6) Jan 11, 2012
The total energy remains zero as does the charge. Zero point energy is the MINIMUM energy level so no one can do diddly with it.
Seems like zero cerrtainly would be a minimum. Although I think you must have some DE hanging around out there somewhere. Maybe that's what makes space expand. It seems someone has done diddly with it. See http://www.physor...uum.html
Seeker2
1.8 / 5 (5) Jan 11, 2012
logic can often produce more than one result.

Really. Where do you come up with this stuff?

Actually you may have a point. Maybe that's where I pick up some strange trojan horse virus. On the other hand maybe someone just wants to sell me web protection. Venture capitalism? Or maybe vulture capitalism. Like the neighborhood kids who steal my tools and then try to sell them back to me.
Ethelred
3.7 / 5 (3) Jan 12, 2012
The problem with those posts is that while it looks like you are joking I suspect you aren't.

It seems someone has done diddly with it. See http://www.physor...uum.html
No they didn't. They used the energy they poured into the vacuum. Read the comments on the thread. There was no free energy there.

That sort of nonsense is why I suspect all those silly posts were actually completely serious.

Ethelred
rawa1
1 / 5 (4) Jan 12, 2012
Seeker2 has many good ideas at times, but I'm missing the underlying concept beneath them. Such an ideas 1) cannot be reproduced independently 2) they're mixing observational perspectives.

For example, when you fall into black hole, you can describe the same situation differently from perspective of inside observer and perspective of observer outside the black hole (so called complementarity of black holes).

http://en.wikiped...entarity

Analogously, in AWT it's possible to describe the water surface from perspective of surface ripples (in which it behaves like thin sparse non-dispersing deterministic environment) or from perspective of underwater waves (in which it behaves like chaotic dense environment). If you will mix these two insights together, then you get into confusing conclusions. This is common situation of many crackpots, who are trying to refuse Einstein or Quantum mechanics, whereas they're just using different observational perspective.
Seeker2
1 / 5 (4) Jan 15, 2012
Gravity is a result of diminished energy density of quantum vacuum caused by the presence of mass. In black hole mass is transforming into energy of quantum vacuum......
http://http://www.spacel...m-vacuum]
Bad link unfortunately
Try http://www.spacel...m-vacuum
Seeker2
1 / 5 (4) Jan 15, 2012
Sorry it should be https://www.econo...omments.
Seeker2
1.8 / 5 (5) Jan 16, 2012
Of course you don't believe in time
What? Who? Did you just make that up?
Seeker2
1.8 / 5 (5) Jan 16, 2012
seems someone has done diddly with it. See http://www.physor...uum.html

No they didn't. They used the energy they poured into the vacuum. Read the comments on the thread. There was no free energy there.


I find no posts at http://www.physor...uum.html about free energy, if that's what you're talking about. Rather " the vacuum is full of various particles that are continuously fluctuating in and out of existence. They appear, exist for a brief moment and then disappear again. Since their existence is so fleeting, they are usually referred to as virtual particles."

"Wilson and his co-workers have succeeded in getting photons to leave their virtual state and become real photons,"

That sort of nonsense is why I suspect all those silly posts were actually completely serious.
Nonsense? Silly? Really? Why don't you read the link before you talk about silly nonsense.
Seeker2
1.8 / 5 (5) Jan 16, 2012
BTW check out

I see no reason to think that anti-matter produces anti-gravity. Positive energy produces gravity and anti-matter has the same positive energy that matter has
Yes all God's critters have positive energy. Even spacetime or the quantum vacuum or whatever you call it. Matter/antimatter pairs even have the same energy. But not the same energy density. And neither has the same energy density of spacetime or there would be no matter or anti-matter. Have I preached this sermon before? Sorry. Anyway you can't say I was preaching to the choir.
Ethelred
4 / 5 (4) Jan 17, 2012
Yes all God's critters have positive energy. Even spacetime or the quantum vacuum or whatever you call it.
Anytime you want to deal with what I said and stop writing pure word wuze let me know.

If anti-matter had negative energy the collision of matter and anti-matter would not release energy. Is that clear enough for you?

Ethelred
Seeker2
1.7 / 5 (6) Jan 17, 2012
Yes all God's critters have positive energy
If anti-matter had negative energy the collision of matter and anti-matter would not release energy. Is that clear enough for you?
So you're saying anti-matter is not one of God's critters?

Ethelred
4 / 5 (4) Jan 17, 2012
Can you read? I said nothing about fantasy critters. You did that.

You can deal with what I said or engage in more fantasy. You seem to prefer fantasy to reality. Have fun but I prefer my fantasy labeled as such instead of pretending it is science.

Ethelred
Seeker2
1.7 / 5 (6) Jan 17, 2012
Can you read?
No. My reading gets all screwed up when I see something like
If anti-matter had negative energy

Ethelred
4 / 5 (4) Jan 18, 2012
Not my fault you couldn't understand that. It was very clear.

If you think anti-matter has negative gravity then, you are requiring it to have negative energy. Apparently you don't understand what you are saying actually means.

Ethelred
Seeker2
1.7 / 5 (6) Jan 18, 2012
If you think anti-matter has negative gravity then, you are requiring it to have negative energy


So common wisdom strikes again. Sorry. Unfortunately negative gravity requires POSITIVE energy density LESS than the energy density of spacetime. So anti-matter floats in spacetime like matter sinks. Ah feels yo pain.
Ethelred
3.7 / 5 (3) Jan 19, 2012
You don't feel my pain. You post word wuze.

If negative gravity required positive energy then the Earth would push matter away.

The energy density of space-time is a variable. Dependent on how much matter/energy is within any point of space-time.

And so far no one has done a test on how antimatter behaves in a gravity field. BUT since it has positive energy, just like matter does, then it would have to have the same gravitational effects.

Ethelred
Seeker2
1.7 / 5 (6) Jan 19, 2012
You don't feel my pain
Hey no pain no gain. No problem.
If negative gravity required positive energy then the Earth would push matter away.
A diamond in the rough. Great intuition! You just proved one of my points: anti-matter pushes anti-matter away. But wait. Earth is not anti-matter. Ergo earth pulls matter in, not away. Minor details. Now I'm going to risk pushing this discussion too far on one post. I assert matter and anti-matter don't react gravitationally. If they did pair production for quark matter wouldn't be possible. Or so it seems. More word wuze I guess. Sorry.
Seeker2
1.7 / 5 (6) Jan 19, 2012
anti-matter pushes anti-matter away.
Actually technically not true. Anti-matter pushes on spacetime. So if spacetime intervenes between two anti-matter particles it gets squeezed from both particles, forcing the particles to separate.
Ethelred
4 / 5 (4) Jan 19, 2012
More nonsense. As usual. No intuition on my part. Just good logic. On yours silliness based on pulling stuff out of your posterior.

Ethelerd
Seeker2
1.6 / 5 (7) Jan 19, 2012
No intuition on my part
Probably true. Maybe pure blind luck. Stick with it though. Maybe you'll stumble onto something worthwhile.
Callippo
1.8 / 5 (5) Jan 19, 2012
I assert matter and anti-matter don't react gravitationally
They do, but you'll need a more precise theory to illustrate it. Anyway, I do agree with your assertion, antimatter particles repel mutually.
Seeker2
1.7 / 5 (6) Jan 19, 2012
I assert matter and anti-matter don't react gravitationally
They do, but you'll need a more precise theory to illustrate it.
More precisely anti-matter pushes against spacetime since its volume is greater than that of an equal energy content of spacetime. Also spacetime pushes against matter since its volume is greater than that of an equal energy content of matter. So spacetime is caught in the middle, pushed from one direction by anti-matter and retaliating by pushing into matter. So spacetime intervenes before anti-matter pushes against matter. Else matter and anti-matter annihilate, each releasing its energy content.
Callippo
1 / 5 (3) Jan 19, 2012
More precisely anti-matter pushes against spacetime since its volume is greater than that of an equal energy content of spacetime
Material observable objects can be pushed only toward another observable objects, outside them every pushing/pulling force is poorly defined. On the other hand, volume of material objects is poorly defined with compare to the volume of space.
Seeker2
1.7 / 5 (6) Jan 20, 2012
pushing/pulling force is poorly defined.
Define them as fields. Yes IMO fields have always been poorly defined. So try defining them as differences in energy density.
Seeker2
1.7 / 5 (6) Jan 20, 2012
Or, per http://www.physor...xy.html,
IMO all particles/forces are basically a result of spacetime being reconfigured and attempting to return to its original state of higher entropy.
Ergo spacetime has memory. Never thought about that.

Ethelred
4 / 5 (4) Jan 20, 2012
Probably true. Maybe pure blind luck. Stick with it though. Maybe you'll stumble onto something worthwhile.
Or it could be what I said, LOGIC. Something you can't seem to handle.

Now why don't you and Zephir talk to each other.

Cranking on two cylinders might shake something loose and one of you two may even try reality for a bit.

Have fun.

Ethelred
Seeker2
1.8 / 5 (5) Jan 20, 2012
Cranking on two cylinders
I love it. Way to score.
TheGhostofOtto1923
3.3 / 5 (19) Jan 20, 2012
I always like to check what REAL scientists think...

"While the overwhelming consensus among physicists is that antimatter will attract both matter and antimatter at the same rate that matter attracts matter... but the hypothesis still open to falsification...The CPT theorem asserts that antimatter should attract antimatter in the same way that matter attracts matter. However, there are several theories about how antimatter gravitationally interacts with normal matter:
Normal gravity: Standard theory asserts that antimatter should fall in exactly the same manner as normal matter.
Antigravity: The theoretical analysis also focused on whether antimatter might instead repel with the same magnitude. This should not be confused with the many other speculative phenomena which may also be called 'anti-gravity'.
Gravivector & Graviscalar: Later difficulties in creating quantum gravity theories have led to the idea that antimatter may react with a slightly different magnitude."
Seeker2
1.7 / 5 (6) Jan 21, 2012
I always like to check what REAL scientists think...
Yea me too. In the meantime I think the evidence for antimatter has sort of floated away, except where it's been trapped in the inner Van Allen belt. But note that when expansion causes the energy density of spacetime to become less than antimatter antimatter will become attractive like matter. But I wouldn't expect to be around when that happens. So in the meantime we'll just have to think about it I guess.