The Inevitability of Physical Laws: Why the Higgs Has to Exist (2012) [video] | Hacker News Reader

The Inevitability of Physical Laws: Why the Higgs Has to Exist (2012) [video]

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29 pointslisper10 comments

~2:35 > "In 2002, he moved to Harvard to become full professor there, and will remain there until he joins our faculty of the institute in 2008"

I don't understand; when was this recorded? The Higgs Boson was discovered in 2012, and he refers to that event. Why is he referring to 2008 in the future tense?

EDIT: It sounds like it is from the later part of 2012.

The original upload is from 29.11.2012 and the lecture was held on October 26, 2012:

https://www.youtube.com/watch?v=hcPW7lyHpIc

Can the OP or the mods please change the link?

Or even better to the original page with the description, and add [2012]

https://video.ias.edu/arkani-hamed-lecture-10-12

HN won't let me change the link, but I did edit the title to include the date.

I'm a native English speaker - I feel it's totally valid to talk about a past event in the future tense as used here. I can't explain why, but I've heard it been used before and doesn't seem ambiguous or incorrect.

Edit: tho the past tense is preferable.

Inconsistently used here, but it's the historical present:

https://en.m.wikipedia.org/wiki/Historical_present

For some reason, I hear a old-style narration over a documentary film when I hear this tense.

Doe anyone know where I could find a more in-depth explanation of why there can only be 0, 1/2, 1, 3/2, 2 spin fundamental particles??

If you're asking about why there's an upper limit to the spin, this Quora thread had some good info (Simmons-Duffin is a top notch expert on field theory): https://www.quora.com/Why-are-there-no-spin-3-2-or-higher-fu... Short answer is that for too high a spin the theories become non-renormalizable and break down [i.e. require additional physics to enter] going to ever shorter length scales.

If you're asking why it goes in steps of 1/2 it's a group representation theory thing (guessing you probably already know about that).

I was mostly referring to the point in the talk where he claims that just relativity and quantum mechanics is enough to imply that there are no spins higher than 2, he kind of skips over that part.

In that view I'm not convinced renormalizability is a strong enough property, since the graviton is famously non-renormalizeable (or so it seems, anyway). But I'll have a closer look at the quora thread; maybe someone has a more 'fundamental' argument.

Good video, thank you!

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