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2013 TV135: 1 in 14,000 impact in 2032

NASA's Near Earth Object Program finally has another candidate rock whose Torino scale is positive, even though it's just 1 so far.

Its name is 2013 TV135. It's been observed for 9 days or so. During the recent hours, the probability of collision on August 26th, 2032 – Witten's 81st birthday (he wishes I would never have used his name in this sentence, but I've already heard this comment from him on 9/11/2001 right after my PhD defense) – has grown from 1 in 48,000 to 1 in 14,000.

What is impressive about the object is the diameter, 410 meters. The mass is 90 million tons and the impact speed is 14.9 km/s. That produces 2.4 gigatons of TNT energy.

Most likely, the probability of impact will start to go down, essentially to zero. However, with the probability 1 in 15,000 or so, it will eventually converge towards 100 percent. ;-)

In the unlikely case that the probability will approach 100 percent, the Torino scale will be upgraded from 1 to 4 and 5 and then 9 and 2032 will be celebrated with some regional devastation, something like an extermination of a country. Such events occur once in 10,000-100,000 years.

2007 VK184 is another rock whose Torino scale is 1. The collision in 2048 has odds 1 in 1,500 but the diameter is 3 times smaller than for 2013 TV135.

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reader Jiri Moudry said...

The impact should happen at Hollywood.

reader davideisenstadt said...

should be "the diameter is one third that of tv135" the time you get one time smaller, youre at zero, lubos.

reader Kimmo Rouvari said...

I wouldn't consider that as a threat ;-) There are two reasons. The first is obvious and I won't repeat it again, active TRF readers know what I mean.

Luckily, we are aware of the bastard! That gives us a chance to destroy it. With current means it can't be destroyed. Nuke blast(s) would most like break it into smaller but as deadly pieces.

We have two options. Evacuate the future ground zero and accept the losses OR we can develop a device which penetrates into the bastard and ignites antimatter bomb. Naturally I would choose the later ;-)

reader Luboš Motl said...

LOL, antimatter bomb.

The difference between H-bomb or other nuclear bombs and an antimatter bomb is that we don't have the fuel for the latter - antimatter has largely annihilated.

So antimatter has to be articially produced and it costs the same huge energy, E=mc^2 (plus overhead for losses), that you want to get out when the matter and antimatter re-annihilates. The only result of this theater is that one improves the energy yield per kilogram by 2 orders of magnitude relatively to the H-bomb, which is not much.

When one breaks such things with a bomb, there may be deadly-if-collided pieces but all of them may go along trajectories that avoid the Earth. That's the point of such operations.

reader Kimmo Rouvari said...

LOL for yourself :-) You don't actually have to create antimatter (based on my hypothesis). Matter is, at the same time, antimatter. It's all about spin orientation of particles towards each other. The best part is that I can prove it. It's hard to argue my model being wrong at ground zero ;-)

reader anna v said...

The option you are not talking about is using a bomb to elastically scatter the thing to a non earth intercepting orbit. Anti.matter bombs are science fiction considering how hard it is to just get an antiproton beam

reader Kimmo Rouvari said...

I can *guarantee* that those are not science fiction for long.

reader lucretius said...

What does the "guarantee" involve? Are you going to commit seppuku if NASA does not confirm your anomaly or what? (I have to add I would be sorry if you felt obliged to go so far ;-) ).

reader Kimmo Rouvari said...

No way Jose! :-) I have other plans.

reader petrossa said...

I'd rather think something like the sahara desert, libya,niger,syria etc. Filled to the brim with medieval warriors hacking of heads

reader Tim Groves said...

Two out of every three incoming objects that reach the earth's surface should hit the sea, so rather than turning a small or medium-sized country into a crater, we're more likely to experience a huge tsunami plus a fair amount of ejecta an aerosol creation. Does anyone have an idea how much damage an ocean hit from a 90-million ton asteroid is likely do do?

reader Gordon said...

"Matter is at the same time, antimatter."

"I don't know what you mean by 'glory,' " Alice said.

Humpty Dumpty smiled contemptuously. "Of course you don't—till I
tell you. I meant 'there's a nice knock-down argument for you!' "

"But 'glory' doesn't mean 'a nice knock-down argument'," Alice objected.

"When I use a word," Humpty Dumpty said, in rather a scornful tone, "it means just what I choose it to mean—neither more nor less.""
--Lewis Carroll --Through the Looking Glass

reader lucretius said...

Actually, I think Kimmo is much more of a simple soul than the sophist Humpty.

Kimmo really seems to believe that all particles can be converted into their own anti-particles by changing their "spin" and that you can do that by means of a pair of magnets purchased in your local hardware store. At least that's what I have surmised from his comments on TRF. I have not read his "papers" since lacking any confidence in my judgement in the matters of physics I will only do so once he becomes famous. Which, according to him, is bound to happen very soon.

reader Kimmo Rouvari said...

I have to clarify things a bit. Different spins are needed but that's just a half of the story. The magic is introduce these two different spin particles spin axes (yes, they actually spin in classical sense!) head-on, causing annihilation. It sounds easy but doing that with sufficient number of particles (aimed to cause self sustained chain reaction) simultaneously requires some skill.

Cobalt is an excellent material due to its nuclear spin (referring to contemporary terminology). It's very easy to control cobalt nucleus orientation with magnets. Again, some skill is needed in order to prevent precession.

reader scooby said...

The big black glass NSA building in Fort Meade gets my vote.

reader tomandersen said...

I went to a talk once that determined that the insurance quote for damage from asteroids should be about $300 million/yr. But that was 20 years ago, so it would now be say $2 billion per year. Chump change for the planet, but we would need an off earth insurance company to take on the policy!

They (can't remember who) used this number as some sort of estimate of about how much money we should spend on avoidance and tracking.

reader Rehbock said...

Look at the preface to the 1930 Dirac Principles of QM. Read the first few chapters of 1996 book "The Second Creation" revised 2nd ed. by Crease and Mann.
Lubos is right on history and foundations of the theory.
Nature declines to commute. That was established 90 years ago. Gell-Mann borrowed "Everything not forbidden is compulsory.". in QM. If in finance if this time is not different, it is because greed requires that everything forbidden is compulsory.

reader Rehbock said...

I second. I have been looking forward to it after Susskind's puzzling remarks a couple of months ago.

reader Luboš Motl said...

Dear Tom, as lucretius says, what I am actually stressing is that there's no return to classical logic because falsification in physics is irreversible and it's always been.

But otherwise your idea that one may predict the future by looking at the history and saying that it must be "analogous" is just silly. My evidence that certain principles of quantum mechanics are here to stay are based on vastly more solid arguments than your vague comparisons with the history.

Your counting "we don't understand 90%" is just silly because knowledge is not measured in kilograms. We understand everything we observe on a daily basis. Concerning those 90%, we know how dark matter and dark energy behave, and that's often everything there is. Moreover, 9 days from now, we may understand what particle(s) the dark matter is composed of, too.

reader Peter F. said...

Especially for Swedish readers:
To me almost anywhere is fine as long as 'TRFare' and their family and friends are not träffade.

reader masmadera said...

Just to me sure that there is no misunderstanding. The rant in the Spanish "newspaper" is written by Echenique-Robba, not by Englert.

reader john said...

Dear , lubos , I fail to understand why do you think that research on the foundations of QM means trying to replace quantum mechanics by ideas from classical physics .

reader Luboš Motl said...

I am not saying it *should* be so. I am just saying that all the people in the real world who describe their research or musings in this way *are* struggling to return to classical physics - by which I mean hypothetical laws describing the state of Nature by an objective collection of information that evolve according to some equations.

The reason why I am saying it is that it is demonstrably the case. If you wish, I can remind you of dozens of names of such "researchers" that fit into this description perfectly.

reader Andrei Patrascu said...

definitely agreeing with the moonlanding :) amazing engineering work!

reader Sab said...

Mr Lubos, first of all, you should now that Pablo Echenique Robba is not that bad scientist. You can check his CV here: Not bad for a young guy.

On the other hand, I didn't read the paper and I'm not going to do it. But, let me say that you affirm a lot of things that are not so clear. You say that QM is the final theory, or, more precisely, probabilistic character of Nature is totally true. Ok, 120 years ago most of physicists thought that classical theory was totally correct. And nowadays we know that QM has overcome CM. Maybe, within 100 years, a new theory will arise without a probabilistic interpretation of Nature. Or maybe not, I don't know it. But we cannot be sure about anything... At least, this is my opinion.

And finally, let me say that you are being quite rude.

reader Dilaton said...

Confirmation by experiment is a good way of shutting the mouth of obstinate tolls, even though physicists may not need it to see what is right...

reader Dimension10 (Abhimanyu PS) said...

I can't find the quote anywhere except in your comment:

reader Dimension10 (Abhimanyu PS) said...

Mr Lubos, first of all, you should now that Pablo Echenique Robba is not that bad scientist. You can check his CV here: Not bad for a young guy.

SO? You think anyone cares about his CV? He's wrong. So he's wrong. Buh.

reader Dimension10 (Abhimanyu PS) said...

reader Dimension10 (Abhimanyu PS) said...

That explains it... All the most interesting posts have been missing since the past three weeks or so.

reader lucretius said...

Well, my copy says:

"Entanglement at a distance" (May 2nd, 2007), L.Motl

The style sounds pure Lubos to me and his name is on it. Maybe there is more to it than mets the eye ;-)

reader Dimension10 (Abhimanyu PS) said...

If you click here, you'll see that it was quoted by Lubos in that lecture, but it was said by Brian Greene.

reader lucretius said...

Why do you think it was said by Greene? It does not say so. It only says that one can find a more popular presentation in a book by Greene. Besides, the English even in the first paragraph although very good, does not sound 100% native. Anyway, Lubos can resolve this if he can remember, but there no suggestion that this is a quote (and even if it is, he obviously agreed with it).

reader Dimension10 (Abhimanyu PS) said...

Did you see the edit?

reader lucretius said...

I saw it now ;-)

reader Gordon said...

Hmm, so he believes that ALL particles are Majorana particles.
Unfortunately, before he becomes famous, he will use the magnets and win a Darwin Award :)

reader Gene Day said...

No, Kimmo, they do not spin in the classical sense

reader lucretius said...

He has indicated that he is trying to avoid this eventuality. I gather Kimmo has also generously offered the right of first bid for his technology to the US DOD but if they turn it down he has "other plans"...

reader Gene Day said...

QM has overcome CM? That is just baloney, Sab. CM is an enormously powerful tool and it will be successfully employed forever.
It was found to be only an approximation, of course, when physicists tried to apply it to things very small or very massive. It is very wrong to say that QM replaced CM; it simply extended CM into into new realms of experience.
QM, however, is not an approximation; it is exact and complete. Your speculations are without merit.

reader Sab said...

Come on... I guess I'm clear enough when saying that QM has overcome CM. Of course CM will be a really useful tool forever and ever. And if you think that QM is exact, you are making the same mistake as physicists did in the nineteenth century. Congratulations.

reader Kimmo Rouvari said...

You seems to have a bad habit of underestimating other people :-) My hypothesis is that particles actually spin. With that hypothesis, TOE opens up ridiculously easily.

I know the meaning of spin in contemporary physics, so save me from your lecture.

reader Luboš Motl said...

Dear Sab, Gene is not making any mistake, surely not the "same one" as folks in the 19th century who thought that classical physics would be valid forever. They were wrong.

Gene says that quantum mechanics is universally valid and he is right so what he's saying is clearly not the same thing. Learn the meaning of the word "same" and/or the difference between right and wrong before you post extra comments on the Internet.

reader Sab said...

Ok, my God. We adore you. You enlighten us.

reader Kimmo Rouvari said...

In your dreams. I would do it properly, no awards given, ever ;-)

reader lucretius said...

I thought you claimed that you could "prove" it. In which case, you shouldn't call it a "hypothesis" but a "theorem".

reader lucretius said...

You also should learn to use sarcasm without embarrassing yourself.

reader Kimmo Rouvari said...

Thanks for the correction :-) Anyway, it looks like that NASA has a quite slow process before publishing the anomalous speed increase in the case of Juno Earth flyby. I have a bottle of champagne in my freezer...

reader Gene Day said...

Oh, you are perfectly clear, Sab, but you are just too stubborn to admit your error. When something or someone is “overcome” the word implies defeat of that person or thing. You are just being bone-headed if you continue to assert that CM has been defeated, replaced or overcome. On the contrary, CM has been enhanced, which is precisely the opposite thing.

I have been studying and working with practical QM problems for 58 years and it is just a fact that QM is complete and exact. Get used to it.

reader Gene Day said...

Simple-minded folks like Sab must first learn to listen but they refuse to take that first step.

reader Mikel said...

Just a minor comment on this bit: "Spain is an inferior nation in the state of complete mess, indeed". Lubos, it will soon be a quarter of a century since you got rid of communism and your country's per-capita GDP still only stands at 14,500 eur, versus Spain's 20,300 eur (2012, EUROSTAT). When are you planning to catch up? By this I'm not saying that Spain is not an accomplished member of the European PIGS group of nations. I'm just pointing out that Czekia is at an even lower state of affairs. Best regards, Mikel.

reader Kimmo Rouvari said...

Your idea inspired me! We can increase object's gravitational interaction with Sun by increasing its spin frequency. Spacecraft utilizing lever increases object's spin frequency to the needed value, that's all.

reader Sami Teeny said...

Lubos - I am kind of new to quantum mechanics so I am trying to get as much good info as possible. I have a quick question about convergence rates for the Born probabilities. Is there a way to calculate how many measurements to get the right probabilities. I read in a crackpot paper over here that this wasn't possible with the standard interpretation of quantum mechanics. Would you care to enlighten me?


reader Andrei Patrascu said...

of course any theory should be taken with some salt and pepper but to say that a theory that predicts reality so well is wrong or incomplete must mean you have some physical results where this theory fails. I speak about non-relativistic quantum mechanics applied in a non-relativistic framework. Where does it fail? Of course, one could design an experiment that will show correctly there are no physical "cat-states" but this is not done precisely because most of the research is focused in proving they really are and the experiments cannot give (in the way they are designed) a clear answer for "no, there are no physical cat states" ... the issue is about how people are looking at the problem. They keep looking at it just in a way that allows them to prolongue the "research" and not in a way that could give a definite answer... although we all know what the answer is... don't forget, quantum mechanics was constructed precisely because experiments did not behave as expected...

reader Andrei Patrascu said...

it is a problem nowadays the fact that scientist do not actually search for answers to questions but search for ways to prolongue their research no matter how far that is from reality. This is mainly due to bad incentives... a science paper is well regarded independent of its quality just because it is in science. I trained myself to judge papers according to their value not according to where they are published and what I see is that in fact scientific progress is still a slow endevour no matter how many papers are published daily or weekly in science, nature or PRL...

reader Andrei Patrascu said...

for several points of view lots of "research" now in "foundations" is like searching for the ether... it is just that after einstein changed the way of looking at the problem people stopped searching for ether in special relativity... not the same happened for quantum mechanics (simple QM)

reader Filigrana said...

I think you are wrong, dear Lubos. Echenique-Robba is not trying to return to a classical description of Nature, but to reach a theory with well-defined postulates, either a modified Quantum Theory or a different one. The postulates of Quantum Mechanics, as defined, for example, in "Mechanic Quantique" by Cohen-Tannoudji, are the basis for all the theory; I am not against their validity, and Echenique-Robba is not either. But some problems arise when we try to understand, for example, the 5th postulate: when an observable is measured, the quantum system collapses. Let me explain why I see this as a problem.

What is a measure? Well, maybe it is the interaction between a classical system and a quantum system... But does it mean that there is a limit to the validity of Quantum Mechanics, that for large systems only Classical Mechanics apply? If this is true, then the problem is to explain how to combine both theories for mesoscopic systems. If not, then classical systems are only large quantum systems, so the Schrödinger equation should apply... But this equation is deterministic, while the collapse is not. This is the measurement problem, and, as it is not solved, any idea that could led to a better understanding should be welcomed.

This postulate is only an example, and there are other 'dark' corners in Quantum Mechanics. And this is my point. No one is trying to destroy Quantum Mechanics, but to understand it. Maybe the solution is given by the decoherence (the interaction between systems leads to the existance of some pointer states that are seen as the result of the measurement), maybe by Echenique-Robba's ideas, maybe by some other proposals, who knows. But no one should feel ofended by these ideas, unless he is too short-minded to think about anything new and rudeness and impoliteness are his only arguments against a hardworking scientist.

One last remark. I do not care who said 'Shut up and calculate!', but the idea of forbidding people to think sounds like religion, not science.

reader Sami said...

Thanks for the explanation. I used "standard quantum mechanics" only to differentiate between the statistical understanding of the theory and the many other "interpretations" that exist, not to give any credence to those other theories.

reader superok4luv2u said...

dear lubos i'm sorry if what i am going to might seem to be off topic but i am starting to read in decoherence and what i understand right now is that the environment + system starts of in a well define PURE state and since after time T for each system eigenstate there corresponds an environment eigenstate that i have no chance of knowing since the number of degrees of freedom is and i reflect that ignorance by partial tracing the whole thing with the environment eigenstates however that ignorance is still classical the environment is still in one of thees eigenstates i just don't know it yet and that lead to the increase in entropy right?
Do i understand it correctly or am i missing something here?

Any response will be greatly appreciated?

reader Gene Day said...

QM, believe it or not, is a final truth. It will never be supplanted by something more accurate because it is exact and complete. Any theory of everything, which string theory certainly is, has to be a quantum theory, otherwise it will necessarily have limited applications.
If you don’t understand this then you will just have to accept it or else be willing to learn.

reader Gene Day said...

No, Bell tests do not alter the fundamentals in any way. That is just wrong, dead wrong.

reader Gene Day said...

Lubos is right, lucretius. Bell’s contributions may be important to your (and others’) understanding of QM but they added nothing to QM itself. QM has been complete for nine decades or so.

reader Gene Day said...

I don’t think Lubos finds it remarkable at all. Neither do I.

reader Gene Day said...

Are you really going to adhere to this untenable position? You are just plain nuts!

reader lucretius said...

I suggest reading the entire thread before posting. If he does not now, at least he did when he wrote these words (and "political correctness" is not a believable excuse).

reader Luboš Motl said...

Right. Bell made the complaints and intuition of EPR from the 1930s explicit, making it more clear what the intuition of EPR - refined under the term of local realism - actually implied about the experiments with entanglement. So it was a very helpful appendix to EPR. But it's been irrelevant for physics because already when EPR wrote their paper - and years before that - it was established that the world is *not* described by a realist theory, local or otherwise, so any more detailed research of local realist theories is at most mathematical research inspired by (outdated/wrong) physics.

The actual reason why it took 30 years for Bell to make the EPR point quantitative was that no competent enough physicist was really interested in revivals of classical or realist theories between the 1930s and 1960s; people just realized that EPR were wrong. John Bell didn't differ by being smarter; he differed by being more excited about realist theories (which is approximately equivalent to, but not the same as, being less smart). So he revived the EPR way of arguing and made these attacks on proper quantum mechanics more popular which is also why his detailed result (Bell's inequality) was suddenly viewed as more important than it was.

reader Luboš Motl said...

No, lucretius, I have already explained what was said to be remarkable. The remarkable thing is that the world is understandable - that science allows us to rigorously establish some results such as the basic postulates of quantum mechanics.

Whether or not the context was more diplomatic or politically correct, the quote surely does *not* say that it was Bell's result or Aspect's experiment that were remarkable.

reader lucretius said...

I agree, but you clearly misunderstood what I meant by a “cultural impact”. It has nothing to do with me or any other individual personally. It is to do with the way certain ideas are received by what constitutes our whole culture, of which physics is a part. In fact these ideas belong more to philosophy than physics.

Before the experiments that confirmed violations of Bell’s inequalities I, like the great majority of educated non-physicists viewed the situation in physics as follows. Although I was not very interested in physics I knew about the Heisenberg Uncertainty Principle - this was what every educated person knew or should have known then. I knew that it stated that two complementary variables could not be known simultaneously. I also knew that there were two basic views among physicists on this issue and two groups of very famous physicists (one of them containing Einstein) who disagreed about the cause of this impossibility. According to one view, both quantities “existed” but could not be simultaneously measured - this was a “problem of measurement”. The other group held the (philosophically shocking) view that the quantities did not actually “exist” until they were measured. The dispute was viewed as unresolved at that time.

I also knew about the EPR “thought experiment”, which was used as an argument by those who claimed that QM was “incomplete”. I remember thinking that the experiment was clearly unperformable, and the dispute seemed to be of a kind that may never be settled (with both sides, remaining, of course, convinced that they were right).

Then Aspect’s and others experiments settled it - and settled it in a direction that forced every informed and thinking person to re-examine the meaning of basic ontology.

The most shocking thing for me was not the actual result, but the fact that it turned out that an experiment of this kind could be performed at all.

It’s consequences were far beyond physics. The violations of Bells’ inequalities are even today discussed at philosophy conferences and not just at the vague level that some scientists associate with all philosophy.

How much credit Bell himself, rather than EPR and the people who performed the experimenters, deserves for this is a different issue. But the Bell’s inequalities certainly occupy a huge place in the history of human thought, even if it is perfectly plausible to teach a complete course of QM without even mentioning them (except, of course, if one wanted to discuss some very interesting applications).

reader Luboš Motl said...

Dear Lucretius,

I have serious problems with pretty much everything you propose in this comment.

We sometimes say that physics is a part of the culture but what we sanely mean is that one can't be a cultural person without some basic familiarity with physics.

But you are interpreting the "physics is a part of culture" in a different way - and it's not the first - in a way that says that physics should obey the rules of the mass culture and decide about the validity of its propositions according to what the public thinks or talks about.

Sorry, this ain't the case. Physics isn't subordinate to the public or the culture in any of these sense. We've had very similar debates in the context of Strassler's populist demagogy concerning the reasons why string theory is being studied.

Physics is a science so it decides about the validity of propositions according to the empirical evidence and valid logical reasoning and calculations applied to the empirical knowledge. Whether most people or most PhDs or most Nobel prize winner understand something at a given point is irrelevant. If they don't understand valid arguments or evidence, they're just not players in the actual physics enterprise, at least not important players, regardless of their influence in the society or degrees or any other sociological properties of this sort.

The Bohr-Einstein debates were clearly resolved at the level of science - Bohr has always been right. All the predictions that the quantum pioneers made were right - even predictions for phenomena that were checked after those quantum pioneers died. They were saying that they understood those issues, i am telling you that I understand these issues, up to a modernization of the formulation, we the "heirs" of them are saying the very same things as the quantum pioneers, and all of our propositions are experimentally confirmed while all differing predictions by any "opposition" has been systematically proven to be wrong.

What more solid proof that Bohr et al. were always right could you ask for? Whether you think that this case may be beaten by confused people as long as the number or political power of these confused people is large enough, then you completely misunderstand what science - and meritocracy and justice, by the way - is all about.

Some results like that - studies of local realist theories that were done after 1920s or even 1930s - may occupy a "huge" place in a history book of human thought but if they do, it is a proof that this history book of human thought is as unscientific as a 21st century book book promoting geocentrism or creationism. One may write a book, buy lots of pictures, and excite millions or billions of people about such things, but they're still scientific rubbish.

In science which is a damn solid human enterprise that is *independent* of human limitations and conventions, the EPR ideas and their by-30-years-younger appendix by Bell simply do not occupy a large place, surely not a "huge place". My QM course dedicated 1/3 of 1 of the 30+ lectures to Bell's theorem - that's about 1% of the QM course and I am telling you that I would have always agreed that such an exposure to the theorem is a significant overstatement of the importance of the theorem on physics - or even, more generally, "reasoning of competent physicists".


reader lucretius said...

The quote said: "and remarkably, we can prove this statement experimentally". That clearly means that the fact that we can settle such matters by experiment is remarkable. That is indeed remarkable, because at one time it seemed that this sort of dispute is bound to remain purely one between theorists - as probably the current disputes about what happens inside a black hole etc. are. But you must admit, that if someone thought of an experimental way to settle these firewall disputes - this fact, that it can be settled experimentally, would be remarkable.

I don't see any sign of political correctness in that old statement of yours Lubos for two obvious reason. First, you are not the kind of person who yields even to very strong pressure. Secondly, nobody would apply any pressure on you to acknowledge the fact that some seemingly purely theoretical ideas (EPR) can actually be tested by experiment.

There is no reason for this dispute at all, because I am not claiming that Bell's inequalities were a remarkable piece of physics, but only agreeing with your old statement that it was remarkable that such a thing could be subjected to an experimental test.

reader lucretius said...

The disagreement between us has nothing to do with physics. It is all to do with what constitutes "culture". Let me give you just one example, that should suffice.
Aristarchus of Samos proposed a heliocentric theory of the motion of planets 1800 years before Copernicus. And, for that whole period this theory was not a part of Western thought and Western culture - in the sense that virtually nobody's thinking, ideas, research etc. etc. were in any way influenced by it. Then Copernicus rediscovered it and made it a central part of our culture.
OK, that's where I end it, if you still don't agree than then there is nothing that can be done about it.

reader Luboš Motl said...

Well, roughly, but decoherence isn't supposed to be an explanation why the entropy increases although these processes are related and they inevitably exhibit the same "arrow of time".

But the entropy is increasing even in classical physics, as long as some microscopic details about the physical system are inaccessible to experiments.

The purpose of decoherence - the tracing over the environment - is to show that the information about the relative quantum phase between the microstates that may appear as results of experiments is disappearing which is why the squared probability amplitudes |a|^2 may be interpreted as probabilities that behave just like probabilities in classical (statistical) physics and the characteristic quantum phenomena such as interference between possibilities for the same system disappear.

reader Luboš Motl said...

Right, the quote said that it may be settled by an experiment but it didn't say that Aspect's experiment was the needed or the first one to do so. The previous 30+ lectures were full of situations where the predictions of QM were settled by experiments done long before Aspect did his.

Aspect's experiment is of course designed to realize Bell's sketch of the experiment and Bell's sketch of the experiment is a particular quantification of what EPR intuitively but incorrectly expected in a particular situation.

But those things are only important if one agrees that EPR were presenting an important alternative to quantum physics and that Bell was an important particular test of that alternative thinking. I strongly disagree with both. Bell just proposed one of infinitely many inequalities that followed from the EPR reasoning, local realism, which is one of several "frameworks" to design candidate theories that had been known to be wrong in the 1930s.

You - and others - are constantly trying to pull Bell's and Aspect's experiment from the context. The context makes it clear that they were not new or qualitatively important for the course that physics took.

The Bell's/Aspect's toy experiment may be helpful to eliminate a particular idea about an alternative to quantum mechanics but that particular idea hasn't really been motivated by anything since the time when experiments started to show that quantum mechanics was inevitably in the 1920s.

reader Luboš Motl said...

Dear Lucretius, I don't believe we differ in the "meaning of culture". What we differ in is the question whether "culture" decides what is scientifically correct, who is correct, and who is a better scientist than others. You're answering this question by a Yes which, I think, shows that you completely misunderstand what science means. The culture has no business to determine right and wrong in science - so the fallacy is already that you introduced the term "culture" into this thread where it has no right to oxidize.

Aristarchus clearly had a priority in heliocentrism over Copernicus. What's your point?

The reason why I don't talk about this man is that I don't know much about him. I've only seen a monochromatic sculpture of him - a man with a beard - and not even a colorful painting. I don't know what he really thought and why. Because I know so little, and because it's clear that his arguments had to be less sophisticated than some arguments in the time of Copernicus, I don't analyze his musings in detail. He's somewhat analogous to an extraterrestrial alien, a different culture.

But of course that if all other things are equal, Aristarchus was a better scientist than his geocentrist contemporaries. To determine whether his being more right was a coincidence or was due to his better thinking, one would have to study the texts of that era much more carefully than I have. I haven't studied the original texts at all; I am no historian and I am not really interested in other cultures too much (although the ancient Greek culture is "partly" our civilization's predecessor). It doesn't make much sense to "compare" folks from vastly different places/planets or eras because they didn't interact in both ways, they didn't really fairly compete. So if we talk about scientific disputes that continue to the present time, of course that we should better talk about the participants who are more connected to the present, like Copernicus.

But with enough knowledge, of course that we may talk about Aristarchus, too. It's completely analogous, just 1800-years-older a history of (pre)scientific thought.

If Aristarchus had really sensible scientific arguments in favor of heliocentrism and many other folks of his time didn't get it, it just proves that they were less capable thinkers/astronomers/physicists than he was, at least when other things are equal. The ignorant folks (geocentrists) could have numerically represented the majority of the ancient Greek culture. And what? They were still wrong. The inability of a society to understand that the Earth isn't the center of the Universe, even though the evidence exists, is something that the society should be ashamed of (although the things it may be proud about may exist and be more numerous). It seems to me that your approach is exactly the opposite. If a majority isn't understanding some evidence, one may just pretend that it doesn't exist and they may "overvote" the people who understand it. Sorry, your system is idiocracy.

reader superok4luv2u said...

First of all thank you for replying to my question ,I'm by no means saying that that's hp the entropy in general decoheres what i meant that's how the entropy of the system increases when it decoheres one thing that I'm struggling with though, Is the process of partial tracing means that the environment is in of that eigenstates that got entangled with the system after evolution by T and not a superposition of it and i just can't possibly know which one and that's why i partial trace ? and if that's the case isn't that the complementarity principle which says that i have to put a boundary some where (in that case between the system and the environment ) and say that the environment behaves classically and no superposition can occur? i'm certain i'm missing something here

reader Luboš Motl said...

Apologies, I don't understand the questions. It was mostly right in the case of the previous comment as well but now we have crossed a threshold beneath which my attempted reply would be almost certainly unhelpful to you.

reader lucretius said...

You seem to be consistently confused between "how things are" and "how things should be". I can't understand how even imagine that I think that "culture decides what is scientifically correct". This is such a distortion of my views that I have to assume that either we just cannot communicate about certain things at all, or that you are deliberately distorting my views in order to seem to win a debate. I believe and hope it is the former since you know as well as I how the communists and their imitators always turn their opponents views into their opposite - before “demolishing” them (and then demolishing the opponents).

So, although I want to end this argument, let me again try to make my views clear.

The only thing that matters in science is truth and if only one single person believes the correct thing, he is scientifically correct, no matter what the whole world thinks. And this is true not only about natural sciences. When, some time, after the fall of communism and the Soviet Union the great Harvard historian of Russia, Richard Pipes was asked how he managed to survive all the years at Harvard, where practically everyone opposed his views on these subjects, he answered: “Imagine yourself living at the time when everyone believed that the Earth is flat. You, through your own research discovered that it is round. You know that no matter what the others think, your view is true and that it will prevail in the end”.

(This is in Pipe’s autobiography although I am paraphrasing because I don’t have the time to look it up).

This is exactly my view, except that I am not so sure that the truth will always win in the end, although of course I hope so.

But what makes culture is a different matter. It is not the ideas that are true but the ideas that are influential. If it was the former, “Islamic culture” would not exists (actually, it hardly exists today, but that’s another matter). The influential ideas throughout history were generally wrong, but they are the ones that shaped society. As more true ideas replaced less true ones, material life generally improved (this is less sure about spiritual life). As for scientific truth, that was of course unaffected. But culture does matter for everyone who has to live in a society.

Anyway, that’s it, I have no idea if this convinced you or not. Like you, I never yield to pressure and there is no way I am going to agree with anything I don’t agree with.

I am really spending far too much time on this blog, which is having a bad effect on my work, so this is definitely my last post on this topic.

(By the way, for those who think making such promises is childish, maybe but this is a psychological issue: only by making a public promise like this can I force myself to stop replying to new posts. So these are definitely my last words on this subject).

reader superok4luv2u said...

Well again thank you for replying to my questions trust me you have been very helpful in showing me that i got a little bit of details right something i wasn't really sure about

reader Luboš Motl said...

I am surely not confusing "how things are" and "how they should be" at all. I am just acting (at least in some situations) in the way in which I *should* be acting - that's what I *should* do. Note that the previous comment is a tautology. People shouldn't be acting ways in which they shouldn't act just because they sometimes do and others do. ;-)

Your views haven't been distorted at all. You have written about 10+ comments about the very same thing - and dozens of very similar comments before you were temporarily banned. The main purpose of these comments of yours is always the same, namely that what is right - and what I/scientists *should* be saying - shouldn't be decided by what I/scientists should be saying (by the actual evidence) but by what the ignorant subset of the mankind and perhaps majority, pompously labeled "culture", prefers. You have applied this paradigm to Strassler's populist demagogy about string theory and now you were using it to distort fair appraisals of the importance or unimportance of Bell's and similar results for quantum mechanics. You're constantly trying to bully me with these things, majorities, cultures, and all this stinky garbage that just doesn't belong to a decent discussion.

Your comments about ideas "influential on the culture" just don't belong to a discussion about science, either. One can't replace the truth by some "influences on the society". Moreover, when we talk about as abstract ideas as conceptual foundations of quantum mechanics or string theory (and even heliocentrism), it's totally obvious that their spreading does *not* affect the material well-being of the society so this whole talk about the material well-being of the society in the context of Bell's inequalities is just another piece of full-fledged demagogy.

It's completely clear why you offer this demagogy. You want to create the impression that the people who pay lip service to the misconceptions held by the majority improve the material well-being. But they don't. When it comes to pure science (one that is sufficiently far from having truly practical implications), neither the proponents of the right ideas nor the proponents of the wrong ideas influence the material well-being of the society. If there's a causal relationship, it goes in the opposite direction: a better material well-being of the society typically allows the people to spend more time by thinking. But even this influence is extremely far from being a universal rule - as the decline of the mass culture in the recent 50 years in which people were increasingly wealthy exemplify.

You have promised that your comment would be the last one about 4 times already and so far, your promises were always been lies. I wonder whether it will be better after the 5th promise.

reader peppermint said...

Landau and Lifshitz 1991,

Most of Course in Theoretical Physics was published in the '50s, except for the last two books in the '80s. Landau died in 1968.

reader Cabone said...

Considering how bad it looked a month ago or even few hours ago, i'm pleased. I want to start a business and now it looks a lot brighter for me. CSSD and KSCM won't be able to **** me over as badly.

One thing not yet mentioned is that the winner might actually be president Zeman. Technocratic government for the next 4 years? I hope he's not that good, LOL. Still, it gives him a lot more power than I'd prefer.

reader Luboš Motl said...

Exactly. Or let's hope that you're right. Good luck with your business.

reader maels said...

I just want to point out that teaching of
physics in Poland in no way affected by Church, as you seem to imply (i know as
i'm student in Warsaw), and that Lucretius is Jewish, as he wrote several
times, so your claim that he is influenced by Church about what science is and what
it isn't, is invalid.

Moreover he is a mathematician and physics enthusiast, which is not really
common in Poland, i think. That makes him a precious ally and i just want to
suggest that his opinions about Bell inequalities, which you clearly despise,
are of minor importance, comparing to his other, valuable contributions.
Actually, he is one of a very few people here who post valuable, nontrivial, insightful

It would be ironic, if he would be banned and people screaming about their
crackpot ideas or those, who only praise you (and you totally deserve it, imho
your blog is the best on the web but I don’t find it necessary to write thanks
or appraisal under every post I found useful, cause it would be repetitive and
boring for other readers, although some readers of your blog apparently find it
ok and downvote everybody whom you find to disagree) were let to stay. Of
course it’s your blog and you make the rules so what I wrote is minor
suggestion. The same applies to lucretius’s comments. I think that it was
essentially his point that you don’t know much about Aristarchus and that you
should know, but because of lack of direct experimental confirmation, there was
no “cultural impact”, as he puts it and that model was forgotten. There was
just not enough bright people than to create critical mass to support research,
and that’s what culture is from view of science. I assumed here that
Aristarchus model was as good as Copernicus one.

And by cultural impact Lucretius didn’t mean that it is what majority thinks,
quite on the contrary, it is promotion of the best ways to solve the problems
and about best didactical resources used to teach small, but non-negligible portion
of society.

So the reason Bell is remembered, is that he let masses (like me) to understand
QM and not only the smartest professional physicists. At my relativity class,
Bell ineq. was presented as ingenious but sort of didactical idea. I actually haven’t
read Bell papers and don’t consider him very important and neither of
instructors here do. I don’t know, maybe in USA everybody worship Bell, but in
Poland they don’t and I bet neither is Lucretius – he just finds it important
because his theorem is concise, sort of mathematical proof of Copenhagen interpretation,
and – as a mathematician – he wouldn’t (I assume) go through lengths of
founding fathers papers to decipher what they meant - he just has different

Concerning QM interp. I think that your posts about Dirac book, Consistent
histories or posts like “the unbreakable postulates of QM” etc. make it
redundant and unnecessary to read any “problems with QM” papers. About this
Pablo’s paper, I stopped reading after he wrote that Gell-Mann said that Bohr
was dead wrong and brainwashed people. For god sake, he was one of leading
fathers of consistent histories interpretation, known as Copenhagen done right,
as you wrote in one of posts!

Concerning Feynman, that’s what Griffiths says in

“When countering prejudices
of this type I think it not

reader maels said...

inappropriate to point out that Feynman, who knew how
to do calculations better than most

of us, was quite forthright in admitting that he did
not understand quantum mechanics as

formulated in the traditional way, and that anecdotal
evidence suggests he was impressed

the new ideas when he first heard them shortly before his untimely death.”

reader 2253 said...

An Alternative Quantum Physics:
First cause=Real Physics (Real cause of phenomena)
Second cause=Observational Physics (Probabilistic QM and generally what we have today).

For the sake of abstract mathematics, Coopenhangen interpretation, prestige of scientific authorities and generally due to the bad habits of human nature, we reached to have what is today is called Quantum Physics. I do not claim that it does not work. It works perfectly but I am not sure they know what is really going on behind the phenomena.

The greatest problem with today's Physics is the abandonment of fundamental logic in favor of abstract mathematics that do not have to do with the real phenomena but with the observations that they can be interpreted according to your setup and prior assumptions and selection, unfortunately.

I have several examples that prove the absurdity of today's understanding in Quantum Physics although it seems to be in accordance with their measurements. I speak always about the real mechanism and some new formulations.

i)Point like nature of particles.
ii)Wave-Particle duality of particles is correct but Physics does not accept that a charged mass is electromagnetic in nature.
iii)Quantum Tunneling. See (ii).
iv)Einstein's Energy-Mass equivalence. What? Yes it is incomplete. See (iii)
v)Coulomb's law. It is also incomplete that gave rise to all those complex theories including QCD and the BCS Theory of Superconductivity.
vi)How BCS speak about Coulomb barrier since the Coulomb force does not have a low or maximum in its expression?
vii)Casimir Force. What? Of course. It has nothing to do with vacuum fluctuation but appears due to the nature of the complete Coulomb force that is consisted from the regular Coulomb and an attractive or repulsive force as depended by the participating charges.

...and much much more..
I am not expecting anyone to consider the above seriously because it is quite evident that rarely people dare to think on their feet. And to be not misunderstood, I mean to think before you eat pre-heated food (science Catering Services).

Whatever science may claims, fortunately the creator gave us mind to think.

reader Nathan Cook said...

What are the chances that the Communists end up in a ruling coalition? Social democrats + communists + Dawn is only 99 seats, is there some other way it could happen?

They seem thoroughly unpleasant. I thought they might be Eurocommunists but no, it's pro-Cuba, pro-North Korea(!), pro-Stalin(!!!).

reader Luboš Motl said...

Time for pills, agent 2253.

reader Alexander Ač said...

Nah Luboš,

"...will bring to the country will be rather catastrophic." - If you read my blog, event in Czechia would be rather inconsequential to the fate of Homo sapiens :-)

reader U.S. said...

You mention Berthold-Georg Englert, and you refer specifically to his article

This article is very clear about locality versus non-locality.

A sentence in Englert's article: "The formalism of quantum theory has the power to predict the probabilities that the events occur, whereby Born’s rule [4] is the link between formalism and phenomenon." makes it clear that Englert is referring essentially to Born's statistical interpretation of quantum mechanics (also called Ensemble interpretation), which is the minimalistic interpretation of QM or may be to the Copenhagen interpretation.

Interestingly, if one looks up on wikipedia the entry "Interpretations of quantum mechanics" ( then there is a table of the most popular interpretations of QM.

In this table both Born's ensemble interpretation (statistical interpretation) and the Copenhagen interpretation are listed at being non-local. Since Englert's article is clearly right with reference to locality (as long as one refers to Born's ensemble interpretation or the Copenhagen interpretation) it means that the authors of the wikipedia article either had a different definition of locality in their mind or their statement is simply wrong with reference to Born's ensemble interpretation and the Copenhagen interpretation. Since those two interpretations of QM explicitly negate that the wave function has a real existence (which is properly presented in the Wikipedia table) it is hard to imagine how one could give a definition of locality so that it makes sense to say that those two interpretations exhibit non-locality.
Of course once a measurement is performed, the knowledge with reference to the state of the system changes instantaneously for any component (far or distant) of the system; however the knowledge changes only for the observer located at the specific location where the measurement is performed, it does not change for any potential observer at a far distant location. Therefore in the Copenhagen interpretation one could be tempted to define non-locality as the phenomenon that the knowledge of the states of a far distant object changes instantaneously--but is this a meaningful definition, or is this unusual definition of non-locality a hindrance to ascertain the truth (German: "was nicht der Wahrheitsfindung dient"). The authors of the Wikipedia article must have had such an unusual definition of non-locality in their mind, otherwise it is hard to understand why they classified Born's ensemble interpretation and the Copenhagen interpretation as non-local.

With reference to some other interpretations listed in the Wikipedia table, I do agree. For example Bohm's theory is non-local, but since Bohm's theory is different from quantum mechanics this is no problem. Likewise, the transactional interpretation with its "backward-in-time" waves seems like a real modification of QM. The von Neumann's interpretation is problematic with reference to the question of locality, since the von Neumann's interpretation assumes that the wave function has a real existence.