String theory is dead. https://arxiv.org/abs/1801.08160

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Anonymous Fri Feb 2 18:55:31 2018 No.9480799 [Reply] [Original]

String theory is dead.
https://arxiv.org/abs/1801.08160

>>	Anonymous Fri Feb 2 18:58:40 2018 No.9480806 >>9480799 Elaborate

>>	Anonymous Fri Feb 2 18:58:53 2018 No.9480807 what's the quick rundown?

>>	Anonymous Fri Feb 2 19:00:15 2018 No.9480811 >>9480807 no extra dimensions confirmed

>>	Anonymous Fri Feb 2 19:01:11 2018 No.9480813 >>9480811 at least not for propagation of gravity

>>	Anonymous Fri Feb 2 19:01:13 2018 No.9480814 >>9480799 >we place limits on the screening scale for theories with D>4 spacetime dimensions, finding that the screening scale must be greater than ∼20Mpc what does Mpc mean?

>>	Anonymous Fri Feb 2 19:02:08 2018 No.9480815 >>9480807 >https://arxiv.org/abs/1801.08160 gravity wave energy didn't leak into higher dimensions

>>	Anonymous Fri Feb 2 19:03:11 2018 No.9480818 >>9480815 >gravity wave energy didn't leak into higher dimensions Why would it?

>>	Anonymous Fri Feb 2 19:04:22 2018 No.9480823 >>9480814 >what does Mpc mean? megaparsecs? https://en.wikipedia.org/wiki/Parsec

>>	Anonymous Fri Feb 2 19:12:33 2018 No.9480846 >>9480814 1 pc = 3.26156 ly 20Mpc = 65231200 ly about 65 million ly

>>	Anonymous Fri Feb 2 19:15:03 2018 No.9480855 https://www.sciencenews.org/article/gravity-doesnt-leak-large-hidden-dimensions > “We’re not in any way ruling out string theory,” Spergel says.

>>	Anonymous Fri Feb 2 19:16:56 2018 No.9480860 >>9480818 ask the string theorists. that's sorta the point.

>>	Anonymous Fri Feb 2 19:22:30 2018 No.9480866 >>9480855 >Sperg

>>	Anonymous Sat Feb 3 14:33:34 2018 No.9482768 >>9480799 Is this a good thing or a bad thing?

>>	Anonymous Sat Feb 3 14:41:01 2018 No.9482793 >>9482768 Is MAHNZ ZAVIZI ZAVIZI a bad thing?

>>	Anonymous Sat Feb 3 14:47:22 2018 No.9482804 >>9482768 String theory is not dead. (And probably won't die until Ed Witten et al have all gotten stakes through their hearts.) But a few of the possibilities seem to be ruled out.

>>	Anonymous Sat Feb 3 14:59:07 2018 No.9482831 guys listen just listen what if the universe is made out of

>>	Anonymous Sat Feb 3 15:00:39 2018 No.9482836 So how does this kill string theory?

>>	Anonymous Sat Feb 3 15:33:32 2018 No.9482916 >>9480799 lmfao string theory gets it's first ever experimental test and it fails completely. Remind me why we believe in this crock of shit?

>>	Anonymous Sat Feb 3 15:46:52 2018 No.9482954 >>9480799 Maybe it only applies to 1D string theory? And why not go with straight 3D particles?

>>	Anonymous Sat Feb 3 15:57:26 2018 No.9482978 >>9482954 Maybe string theory is bullshit?

>>	Anonymous Sat Feb 3 16:32:23 2018 No.9483066 >>9480799 Is it Motl, the /pol/tard?

Anonymous Sat Feb 3 16:40:22 2018 No.9483086

>>9480799

>https://www.sciencenews.org/article/gravity-doesnt-leak-large-hidden-dimensions

>A variety of theories predict extra dimensions of spacetime into which gravity could leak, but the new result applies only to large extra dimensions, Spergel says.

Does not rule out String theory at all, retard

>>	Anonymous Sat Feb 3 21:20:46 2018 No.9483649 >>9483066 Motl doesn't shitpost on kyrghyz regional yak-milking league forums. Apart from his blog and the occasional mania on quora, he trolls the climate alarmists and anti-stringists on their blogs. Long live string theory!

Anonymous Sat Feb 3 21:31:46 2018 No.9483677
File: 22 KB, 485x443, 123587634.png [View same] [iqdb] [saucenao] [google]

ITT: OMG YOU GUYZ string theory is dead, but fuck you if you expect me to know what string theory even is lmao

>>9480815
>>9480818
my uncle showed me how to patch a leaky water heater once, is this basically what the physicalists did to stop the gravities from leaking

Anonymous Sun Feb 4 04:52:51 2018 No.9484206

>>9480799
>>9480814
>we place limits on the screening scale for theories with D>4 spacetime dimensions

Stupid question, but how can our 4D spacetime be curved (by massy objects) if it doesn't lie in a 5D coordinate system?

E.g. a piece of paper can be flat, the it's possible that it really exists in a universe with only 2 spacial dimensions. But if you say it's curved, there need to be a 3rd spacial dimension into which it can curve.

What am I not understanding?

>>	Anonymous Sun Feb 4 05:05:00 2018 No.9484215 >>9484206 It only affects metrics, space itself doesn't exist.

>>	Anonymous Sun Feb 4 05:13:17 2018 No.9484223 >>9483649 He posts on /r9k/.

>>	Anonymous Sun Feb 4 05:24:21 2018 No.9484234 >>9484215 elaborate

>>	Anonymous Sun Feb 4 05:34:08 2018 No.9484243 >>9480806 read the fucking paper maybe?

>>	Anonymous Sun Feb 4 05:38:53 2018 No.9484248 File: 127 KB, 645x729, b90.png [View same] [iqdb] [saucenao] [google] >>9484206 >HoW cAn OUr 4D sPacEtImE bE cUrVed (by MAsSy ObJeCtS) iF iT DoeSn'T LiE iN A 5D cOORdInAtE SyStEm?

>>	Anonymous Sun Feb 4 05:53:02 2018 No.9484262 >>9484206 >reddit spacing >retarded question

>>	Anonymous Sun Feb 4 06:02:21 2018 No.9484272 >>9484262 >>9484248 You guys are fucking retarded. https://en.wikipedia.org/wiki/Five-dimensional_space

>>	Anonymous Sun Feb 4 08:33:19 2018 No.9484446 >>9484223 explain pls. this is too good

>>	Anonymous Sun Feb 4 08:44:46 2018 No.9484466 >>9484272 something can be curved without having to be embedded into a higher dimensional space, you mong

>>	Anonymous Sun Feb 4 08:46:03 2018 No.9484469 >>9480799 Motl is the single most slavic-looking person I've seen.

>>	Anonymous Sun Feb 4 08:53:28 2018 No.9484477 >>9480799 How does a brainlet like myself goes about asking for an explanation of why in layman terms?

Anonymous Sun Feb 4 09:09:16 2018 No.9484495
File: 76 KB, 937x629, bkne240520110044-mini.jpg [View same] [iqdb] [saucenao] [google]

>>9484466
So you are telling me there are huge mountains and deep valleys inside this meadow? Then why do I need the same amount of time and energy to walk a straight line of 100m on this meadow, no matter where, no matter in which direction?

>>	Anonymous Sun Feb 4 09:11:20 2018 No.9484498 >>9480799 >arxiv Disregarded.

>>	Anonymous Sun Feb 4 09:17:57 2018 No.9484510 File: 388 KB, 1920x1080, Screenshot_2018-02-04-08-17-01.png [View same] [iqdb] [saucenao] [google] >>9484495 Absolutely...but first define what you consider "huge" and "deep". https://youtu.be/eN24Sv0qS1w

>>	Anonymous Sun Feb 4 09:20:39 2018 No.9484512 >>9484495 I don't know and I can't answer that question, but that's how it is because science says so!

>>	Anonymous Sun Feb 4 10:13:24 2018 No.9484602 File: 95 KB, 748x1050, 0.2.png [View same] [iqdb] [saucenao] [google] >>9484510 "huge" -> curvature of at least -0.2 in both dimensions of the meadow "deep" -> curvature of at least 0.2 in both dimensions of the meadow

Anonymous Sun Feb 4 10:33:55 2018 No.9484635
File: 8 KB, 240x160, blank-sheet-paper-wooden-table-empty-39123870.jpg [View same] [iqdb] [saucenao] [google]

>>9484495
>>9484602
Alright, thought about it. What I'm saying here is that if there is an additional dimension, you should be able to notice a curvature of a lower dimensional object in at least one of realities additional dimensions.

But other anons before just claimed that there can be curvature in n-dimensional objects even though there is no (n+1)-th dimension. But I have another example for that. See pic related. Think of it as a piece of paper that is glued to the table. The paper is a 2D object and because it is glued to the table, it also has no way of leaving a 2D space. The paper basically exists in a 2D world. However, us humans have 3 dimensions available and as we look at it, we can say that the paper has a curvature of 0 at any point. If it had any curvature != 0, we would see it in the 3rd dimension, as demonstrated by the meadow example. Now try to give the paper a curvature without requiring it to leave its 2D-only-world, e.g. without somehow removing the glue and pulling it from the table. Pro tip: you can't.

Not saying I'm right and you are wrong, but what is inaccurate about my examples. I just want to understand.

>>	Anonymous Sun Feb 4 12:32:40 2018 No.9484854 >>9484446 It's a meme. He doesn't visit 4chan.

>>	Anonymous Sun Feb 4 12:36:53 2018 No.9484863 >>9480799 string dead is theory.... MAHNZ

>>	Anonymous Sun Feb 4 13:48:31 2018 No.9485045 >>9484243 Do you seriously expect me ro read a 7 page paper just so you can shitpost at level with me?

>>	Anonymous Sun Feb 4 14:22:56 2018 No.9485144 >>9482916 Because it gave "Science Fans" something else to masterbate to.

>>	Anonymous Sun Feb 4 14:34:56 2018 No.9485196 >>9484446 >>9484854 behold https://desuarchive.org/r9k/thread/18929562/#18929722

>>	Anonymous Sun Feb 4 14:38:18 2018 No.9485205 >>9480799 The author of this paper is not only American, which makes the quality of his conclusions inherently dubious (Amerilard physicists are some of the worst), but he's also a graduate student

Anonymous Sun Feb 4 14:41:10 2018 No.9485210

>>9484635
this is the content of Gauss's Theorema Egregium in part. You can determine the curvature of your space without ever leaving your space. This means you never have to refer to your space from some external flat space.

For instance, another space that is difficult to grasp is the surface of a klein bottle with no curvature anywhere.

>>	Anonymous Sun Feb 4 14:49:02 2018 No.9485241 >>9484206 you need to study modern differential geometry (keyword: manifold)

>>	Anonymous Sun Feb 4 18:30:53 2018 No.9485860 >>9485210 >>9485241 thanks. But can you explain what is wrong with my experiments? How to bring curvature in a paper without having it to partly move in the 3rd spatial dimension?

Anonymous Mon Feb 5 06:48:16 2018 No.9487141

>>9485860
>How to bring curvature in a paper without having it to partly move in the 3rd spatial dimension?
You can't: the paper is part of 3D space, so any sort of transformation on it takes place within this larger space.
However, I can mathematically define curved surfaces without reference to any higher dimensional space that they live in, using differential geometry.
>>9480813
Except in string theory gravity is quantised and the extra dimensions are very small and compact, meaning gravitational waves moving through the extra dimensions have to have exceedingly high momentum: the extra dimensions essentially become frozen out. All they've ruled out are large extra dimensions, but we knew that already.

Anonymous Mon Feb 5 07:47:05 2018 No.9487210

>>9484477
Mathematicians define curvature as either "intrinsic" or "extrinsic".

A curled sheet of paper remains "flat" insofar at 2-dimensional beings living on the paper can tell. No measurement they can make will tell them they've been curved into a 3rd dimension.
On the other hand, if you try to make the paper conform to a section of a globe, you can't do it. The sheet must either be torn or overlapped to make it fit. That's why all 2D maps of Earth necessarily distort the world in one way or another.
Our world looks "flat" to us as seen from eye-level, but surveyors quickly find that flat (or Euclidian) geometry doesn't work. The interior angles don't add to 180 degrees. It's unnoticeable when the triangles are small, but the discrepancy gets worse and worse as you measure larger areas. That's "intrinsic" curvature.

Intrinsic curvature is a property of the surface itself. Nothing to do with possible "higher" dimensions it might be "embedded" in.

As several others have pointed out, look up "manifolds" for further details.
For a good, non-technical explanation of non-Euclidian geometries (and a very amusing one) I recommend "Flatterland" by Ian Stewart.

>>	Anonymous Mon Feb 5 18:57:33 2018 No.9488568 >>9485196 ahahahahahaah holy fuck this is awesome. "Mr. Supreme Gentleman, I present you the Supreme Intellectual"

>>	Anonymous Mon Feb 5 20:52:13 2018 No.9488798 >>9480799 It's been dead for years

>>	Anonymous Tue Feb 6 03:03:25 2018 No.9489527 File: 355 KB, 1775x1788, gravitylarp.jpg [View same] [iqdb] [saucenao] [google] >>9480799 gravity is dead

>>	Anonymous Tue Feb 6 03:23:11 2018 No.9489557 File: 116 KB, 720x269, Untitled.png [View same] [iqdb] [saucenao] [google] When you see quotation marks around an imprecise word like this, this early on, you know you're in for some good shit

>>	Anonymous Tue Feb 6 03:29:33 2018 No.9489561 please let it die completely

>>	Anonymous Tue Feb 6 04:26:55 2018 No.9489607 >>9485196 >that Motl mention out of no where hahahahahaha this is great

>>	Anonymous Tue Feb 6 05:59:39 2018 No.9489697 >>9485196 You missed the bit where lumo hates Nietzsche and insults the intellect of Erdös. If it was really him, he would mention Dirac without a doubt.

>>	Anonymous Tue Feb 6 06:22:20 2018 No.9489719 >>9482978 Then what do you propose instead of String/M-theory, and why?

>>	Anonymous Tue Feb 6 10:08:12 2018 No.9489919 >>9484206 Curvature is an intrinsic property of the space and it therefore doesn't rely on being embedded in some larger 'ambient' space.

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