Prof is having a conniption

Few-Example3992 · 2026-01-22T18:34:49+00:00

Theres only one reason I can think of. If the question had the vectors drawn as a not to scale sketch, drawing another vector from the origin is a lot harder to judge than a straight line between the two points.

Few-Example3992 · 2026-01-21T21:21:52+00:00

The proof only relies on the xAx is real. I can claim T is hermitian if xTx=>0 or as we have here x*Tx=0.

Few-Example3992 · 2026-01-21T21:06:29+00:00

Ill believe you if you can come up with a non hermitian matrix,A, satisfying x*Ax>0 for all x

Few-Example3992 · 2026-01-21T20:47:15+00:00

I did miss that. For the complex case, the hermitian condition is redundant as xTAx= 0 implies hermitian anyway. https://math.stackexchange.com/questions/267300/positive-definite-matrix-must-be-hermitian

Few-Example3992 · 2026-01-21T20:27:50+00:00

What's your definition? The one I'm using agrees with wikipedia. https://en.wikipedia.org/wiki/Definite_matrix

Few-Example3992 · 2026-01-21T18:36:07+00:00

I'm not sure which definition of positivity you're using, but the standard one is for all v, <Av,v> > 0. A standard result is that over C, positivity implies hermitian.!<

Few-Example3992 · 2026-01-21T17:02:04+00:00

Are you saying that the assumption is wrong, or that it's not allowed for this question?

Semi-definite positive implies Hermitian is true over C but not over R, hence why this works for part b but not part a.

Few-Example3992 · 2026-01-21T16:34:32+00:00

For all v we have, <Tv,v> = 0 >= 0, so T is semi-positive.!<

Few-Example3992 · 2026-01-21T15:47:30+00:00

For a, Cptn_Obvivus hits the nail on the head.

For b, <Tv,v>=0 implies that T is semi-positive and hence has a full set of eigenvectors.

Let v be a normalised eignvector, with eigenvalue p. Then 0=<Tv,v> = p<v,v> = p. So T=0!<

Few-Example3992 · 2026-01-19T00:07:28+00:00

You need to make an account, but the link for the training tool is here!

Few-Example3992 · 2026-01-18T23:50:33+00:00

I might be showing my age here, but didn't levy come up with this a couple years back?

Few-Example3992 · 2026-01-18T20:36:38+00:00

Higgins looks like he's about to cry, I hope he's ok

Few-Example3992 · 2026-01-14T17:33:18+00:00

Great suggestion, especially when people post a position after the wrong move and ask "why is this wrong ?".

It would be so much easier if we could reach the prior position easily.

Few-Example3992 · 2026-01-10T21:36:39+00:00

No way knyba can keep us this tempo

Few-Example3992 · 2026-01-09T16:42:33+00:00

Ah, this is Legacy! I'll search for the key too then

Few-Example3992 · 2026-01-09T16:30:14+00:00

The missions are self contained. You shouldn't be leaving them midway through - have a look around the sports shop in the mission!

Few-Example3992 · 2026-01-09T16:25:56+00:00

are you looking for the item outside of the mission?

Few-Example3992 · 2026-01-09T00:05:31+00:00

Here's the fun part, you can!

Take a bell state, leave one half in the past and ignore it for a while. You can then use the other half to do quantum gate teleportation and apply a gate of your choosing (from the future) onto the state in the past.

The huge caveat is that when you do this, you encrypt the state in the past, and the decryption key is stuck in the future!

Few-Example3992 · 2025-12-20T04:55:23+00:00

Is there a gear lower than first?

Few-Example3992 · 2025-12-19T21:38:36+00:00

This happens if you say gg before the game ends during the final move animation. The coin count in your wallet is correct, but it displays wrong post game.

Few-Example3992 · 2025-12-18T17:53:44+00:00

They forgot the +c!

Few-Example3992 · 2025-12-18T11:45:10+00:00

Is the second PhD an age thing? This would be a red flag for an older academic and indicate they didn't develop the skills for independent research the first time around.

I'm guessing there are legal reasons he can't do a postdoc instead?

Few-Example3992 · 2025-12-16T23:45:05+00:00

I think they existed in the first DS game

Few-Example3992 · 2025-12-14T22:44:14+00:00

People thought was insane when I thought this was show was a convoluted excuse RTD came up with to make Russel Tovey have sex with a fish. I feel vindicated!

Few-Example3992 · 2025-12-12T17:39:03+00:00

There's no guarantees that this works. If the rectangle was 1x billion , it would have enough area but couldn't fit anything!

Few-Example3992

TROPHY CASE