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At Multiverse Impasse, a New Theory of Scale

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Re: At Multiverse Impasse, a New Theory of Scale

#91

Post by lutusp »

sampo wrote: post #39
lutusp wrote: post #34

Earlier quoted context omitted.

Please have some perspective. Human beings have existed in roughly our present form for 200,000 years. In another 200,000 years, chances are we won't recognize ourselves. And in 5 billion years, which is 25,000 times farther into the future, there will be nothing remotely resembling human beings . We won't be a distant memory, we won't be a memory at all.

That was my point. Natsu was worrying about the ability of a technological civilization to function near the heat death of the universe. Which is much further than 5-6 billion years away. A more "immediate" problem is the death of our own Sun. Of course, what you say is even more immediate.

> Natsu was worrying about the ability of a technological civilization to function near the heat death of the universe.

Unless by "heat death" he meant a cold death, current thinking has it that the universe will gradually cool off, and ultimately freeze, because of the endless expansion provided by Dark Energy.

The fact that the universe is expanding exponentially, i.e. with a positive second derivative, was the first shock. The second came when the implications of this observation began to sink in.

Re: At Multiverse Impasse, a New Theory of Scale

#92

Post by redraga »

angersock wrote: post #88
MisterMashable wrote: post #74

There's a very subtle undertone of negativity in this article about physics. Before I get into, William Bardeen is not in the same league as 'Surfer Dude and his E8 Theory of Everything' which throws basic facts about representation theory out the window, coming up with 'todalay boogus' arguments which amazes auntie, mommie and magazine editors but a real physicist would instantly dismiss. Bardeen is the real deal. H…

So, erm, what does that buy us? I'm just an engineer, so I'm not sure I see the utility in any of that--sorry to sound closed-minded, but am genuinely curious.

A lot of discoveries do not have immediate uses and some might indeed never have any applications. But discoveries can spurn others in unexpected ways. The most famous example of course if the WWW which came out of CERN, a pure physics research institution. Cryptography is another example that has had a profound impact on information security. But the most compelling reason, at least to me, is we investigate because we can! That is just human nature.

Re: At Multiverse Impasse, a New Theory of Scale

#93

Post by MisterMashable »

jwuphysics wrote: post #84
MisterMashable wrote: post #74

There's a very subtle undertone of negativity in this article about physics. Before I get into, William Bardeen is not in the same league as 'Surfer Dude and his E8 Theory of Everything' which throws basic facts about representation theory out the window, coming up with 'todalay boogus' arguments which amazes auntie, mommie and magazine editors but a real physicist would instantly dismiss. Bardeen is the real deal. H…

I study astrophysics, so I won't be able to say much about SUSY or string theories or conformal field theories. I do agree that we're living in a golden age of physics! But your second and third points, inflation and SUSY-- those are definitely not confirmed. In fact, the primordial gravitational waves from BICEP2 are almost certainly dust contamination signal (e.g., http://arxiv.org/abs/1405.5857 ). The discovery of…

Not confirmed in the sense that many in the community are denying the result, which is as it should be. Even considering many models including dust a robust result remains. I think PRL and others are being unreasonably pessimistic but the only way to settle this is for there to be more experiments at different frequencies. Then they can move from the shock and denial phase onto the grieving process. BICEP scooped Planck, big time. It doesn't matter to me but it matters a whole lot to some people and the degree of sour grapes and poor sportsmanship is really stunning. Yes, I am saying a good deal of this is motivated by the tiny team beating the much bigger team though I absolutely disagree with their hypercompetitive interpretation of the whole enterprise of experimental physics. History will tell us that BICEP got lucky, very lucky and they got there first. The dust up is happening on Earth not in space and the latter is certainly much easier to explain away and still have at least a six sigma result. I've read the dust papers with an open mind and none of them add up.

Regarding SUSY, strictly speaking no particles have been directly detected but anomalous currents abound and just about everything seen works perfectly with light SUSY and much better than with the standard model. The dilepton events alone are very compelling. http://www.science20.com/a_quantum_diaries_survivor/a_susy_e... SUSY is in plain view much the way the Higgs was in plain view for about a year before the official announcement. I have no special insider information, just a humble internet connection to download the important papers and a decent knowledge of particle physics. In hind sight, everyone will say 'of course' which always happens. From a theory point of view, SUSY is simply not an option unless there is some spectacularly new theory out there with novel concepts to replace QFT. The Coleman-Mandula theorem is extremely compelling. It basically tells us accept SUSY or find something to replace QFT. Since QFT works and there's no good reason to move on to something else (especially when something else doesn't exist presently and possibly never will), it's a safe bet SUSY must exist somewhere. It just so happens to be light SUSY and we're seeing it at the LHC right now. I think we're presently seeing the equivalent of a COBE picture of SUSY and next year it will sharpen up into a WMAP picture.

Re: At Multiverse Impasse, a New Theory of Scale

#95

Post by MisterMashable »

evanb wrote: post #83
MisterMashable wrote: post #74

There's a very subtle undertone of negativity in this article about physics. Before I get into, William Bardeen is not in the same league as 'Surfer Dude and his E8 Theory of Everything' which throws basic facts about representation theory out the window, coming up with 'todalay boogus' arguments which amazes auntie, mommie and magazine editors but a real physicist would instantly dismiss. Bardeen is the real deal. H…

Do you have any rumors or specific knowledge (even if it's not something you'll share) regarding SUSY? They found missing energy? A new plethora of resonances? Higgsinos or sfermions? Something more exotic?

The dilepton events are the best evidence yet IMO

Re: At Multiverse Impasse, a New Theory of Scale

#96

Post by hcarvalhoalves »

> Perhaps the fundamental description of the universe does not include the concepts of “mass” and “length,” implying that at its core, nature lacks a sense of scale. This little-explored idea, known as scale symmetry, (...)

Isn't the word for that fractal?

Re: At Multiverse Impasse, a New Theory of Scale

#97

Post by differentView »

derefr wrote: post #89
jwuphysics wrote: post #84

Earlier quoted context omitted.

I study astrophysics, so I won't be able to say much about SUSY or string theories or conformal field theories. I do agree that we're living in a golden age of physics! But your second and third points, inflation and SUSY-- those are definitely not confirmed. In fact, the primordial gravitational waves from BICEP2 are almost certainly dust contamination signal (e.g., http://arxiv.org/abs/1405.5857 ). The discovery of…

> The discovery of supersymmetric particles would also be extremely shocking to me, since my institution is heavily involved in CERN LHC experiments, and I haven't heard any hints of a discovery yet. Why does an absence of evidence imply that the arrival of evidence would be shocking? They're doing the experiment because they already believe things are this way and they're trying to get evidence to confirm it. If the…

>They're doing the experiment because they already believe things are this way and they're trying to get evidence to confirm it.

Hypothesizing is one thing, but to believe without evidence is just blind faith.

Re: At Multiverse Impasse, a New Theory of Scale

#98

Post by lutusp »

derefr wrote: post #89
jwuphysics wrote: post #84

Earlier quoted context omitted.

I study astrophysics, so I won't be able to say much about SUSY or string theories or conformal field theories. I do agree that we're living in a golden age of physics! But your second and third points, inflation and SUSY-- those are definitely not confirmed. In fact, the primordial gravitational waves from BICEP2 are almost certainly dust contamination signal (e.g., http://arxiv.org/abs/1405.5857 ). The discovery of…

> The discovery of supersymmetric particles would also be extremely shocking to me, since my institution is heavily involved in CERN LHC experiments, and I haven't heard any hints of a discovery yet. Why does an absence of evidence imply that the arrival of evidence would be shocking? They're doing the experiment because they already believe things are this way and they're trying to get evidence to confirm it. If the…

> They're doing the experiment because they already believe things are this way and they're trying to get evidence to confirm it.

That's not science, that's confirmation bias. In science, one would want to look for evidence that one's theory is false with as much vigor as a search for evidence that it's true. Science isn't law, and it's not religion.

> If they disconfirmed it, that'd be surprising.

If they falsified their theory while only seeking confirming evidence, yes, that would be surprising. This is why open-minded scientists try to avoid assuming what they should be proving (the real meaning of the expression "beg the question").

Re: At Multiverse Impasse, a New Theory of Scale

#99

Post by nilaykumar »

angersock wrote: post #88
MisterMashable wrote: post #74

There's a very subtle undertone of negativity in this article about physics. Before I get into, William Bardeen is not in the same league as 'Surfer Dude and his E8 Theory of Everything' which throws basic facts about representation theory out the window, coming up with 'todalay boogus' arguments which amazes auntie, mommie and magazine editors but a real physicist would instantly dismiss. Bardeen is the real deal. H…

So, erm, what does that buy us? I'm just an engineer, so I'm not sure I see the utility in any of that--sorry to sound closed-minded, but am genuinely curious.

It doesn't buy you anything, just as fine art and music do not buy you anything.

Re: At Multiverse Impasse, a New Theory of Scale

#100

Post by kimdouglasmason »

kazinator wrote: post #78

WOBAD! http://www.theonion.com/articles/worlds-top-scientists-ponde...

From the article:

"That shit would be too much," Gupta said. "It'd be like that Dr. Seuss book Horton Hears A Who and shit. I read that when I was, like, six, and it totally weirded me out."

Nailed it.

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