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Silly Goose
Silly Goose
1:52 AM
is there a formalization of the opposite of an anomaly?
To my understanding an anomaly occurs when a dynamic symmetry of a classical action fails to lift to a dynamic symmetry of a quantized version of the action.
By opposite, I mean the situation when a dynamic symmetry of a quantum action fails to be a dynamic symmetry of a classical version of the action. This seems to happen in Chern-Simons theory, for example.
 
1 hour later…
Silly Goose
Silly Goose
2:59 AM
separate question: consider a system of two spin-1/2s. We have two isomorphic representations associated to this system: (1) a tensor product representation $1/2 \otimes 1/2$ and (2) a direct sum representation $0 \oplus 1$. Are expectation values independent of isomorphic representations?
That is, given an abstract state $\lvert \psi \rangle$ and an abstract operator $\hat{O}$ is $\langle \psi \lvert \hat{O} \lvert \psi \rangle_\otimes = \langle \psi \lvert \hat{O} \lvert \psi \rangle_\oplus$?
If so, then aren't Bell inequalities a way to detect entanglement independent of the tensor product factorization of Hilbert space you are working with?
 
1 hour later…
Sanjana
Sanjana
4:32 AM
@SillyGoose At the level of solutions, spontaneously broken classical symmetries are often restored when we go to the quantum version of the problem. E.g. In classical double well potential, if your state lies in one of the minima, the $\mathbb{Z}_2$ symmetry is broken, but in QM, tunneling between vacuua leads to restoration of symmetries at the level of certain solutions
@SillyGoose Also there's Quantum triviality. But who cares? I know you wouldn't reply :(
Silly Goose
Silly Goose
@Sanjana oh no what do you mean
Sanjana
Sanjana
4:51 AM
@SillyGoose You don't typically reply nowadays. So I thought that you have blocked me for some reason...
Silly Goose
Silly Goose
oh no i have never blocked you i haven't been in hbar very much lately i have been on break and now trying to get immersed into a new project :)
user 85795
user 85795
h o n k
 
1 hour later…
ACuriousMind
ACuriousMind
5:59 AM
@SillyGoose I don't know what the subscripts there are supposed to denote - unless you write the states explicitly as tensors or sums, there's no effect of "thinking about" the space as either a tensor product or a direct sum at all
So I guess that's a: yes, the expectation values are independent :P
@SillyGoose why would they be? I don't see how the Bell inequalities would prevent the existence of some factorization where the states are not entangled (but the operators the inequalities are about won't neatly factor into operators on the factors of that factorization)
Sanjana
Sanjana
6:24 AM
@SillyGoose oh
PM 2Ring
PM 2Ring
6:44 AM
@SillyGoose You may find it useful to read Bell's classic, "Speakable and Unspeakable in Quantum Mechanics", if you haven't read it already. It's not a large book. It's a collection of papers / essays, and it mostly focuses on the philosophical issues, not the mathematics. IIRC.
It was very influential, and I expect that a majority of physicists (and philosophers) interested in the Bell inequalities have read it, or are at least familiar with its key papers. I read it ~30 years ago, so I'm a bit fuzzy on the details. ;) It may help you to better appreciate the motivations of others in the field.
Ryder Rude
Ryder Rude
Bell supported Bohmian mechanics for some reason
it's very clear that QM isnt a general relativistic theory, so all interpretations are incorrect
 
3 hours later…
More Anonymous
More Anonymous
9:35 AM
@user85795 Ive noticed users use this honk ... why so?
user 85795
user 85795
That's the sound a silly "goose" makes :-)
@MoreAnonymous
user 85795
user 85795
10:36 AM
honk
Ryder Rude
Ryder Rude
11:01 AM
Oxyrhynchus Hymn | Ancient
►
05 First Delphic Hymn to Apollo
►
most early songs used to be religious
 
4 hours later…
Bohemian relativist
Bohemian relativist
3:29 PM
is information geometry used in geometrical deep learning?
 
6 hours later…
Bml
Bml
9:31 PM
Hi everyone. A person is inside a boat on a pool and throws a 20 kg steel anchor from the boat into the water. What happens to the water level? Does it rise, fall, or remain unchanged? It sounds super simple, but I can't come up with a quantitative answer... Could you please help me?
Sir Cumference
Sir Cumference
10:28 PM
Waluigi effect
In the field of artificial intelligence (AI), the Waluigi effect is a phenomenon of large language models (LLMs) in which the chatbot or model "goes rogue" and may produce results opposite the designed intent, including potentially threatening or hostile output, either unexpectedly or through intentional prompt engineering. The effect reflects a principle that after training an LLM to satisfy a desired property (friendliness, honesty), it becomes easier to elicit a response that exhibits the opposite property (aggression, deception). The effect has important implications for efforts to implement...
apparently waluigi memes are infiltrating AI research
well, at least to the extent of getting phenomena named after him

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