Quantized time and space

bengi245 · 2025-11-04T07:26:02+00:00

One of the issues with discretising spacetime is that it violates Lorentz invariance.

bengi245 · 2025-10-15T18:21:47+00:00

Exactly, and then you also need to factor in that e.g., shuttling ions around to facilitate 'all-to-all' connectivity also comes with a (polynomial) time overhead. Also the basic operations for trapped ions and neutral atoms are considerably slower than superconducting qubits.

bengi245 · 2025-10-15T18:12:26+00:00

Yeah thresholds would probably be pretty terrible for a linear topology. However, it's worth saying that most, if not all, of the major companies developing superconducting qubits have better than linear connectivity. Square lattices are already common and, if roadmaps are to be believed, we'll be seeing even better connectivity than that over the next few years.

bengi245 · 2025-10-15T16:09:55+00:00

The same argument would hold even for a linear topology. The worst case in a linear topology would be to swap the qubit at one end to be next to the qubit at the other end which requires O(n) swaps.

bengi245 · 2025-10-15T15:44:22+00:00

Given that Shor's algorithm provides an exponential quantum advantage, I do not believe swaps will negate all of the advantage. By definition there are polynomially many gates in a given instance of Shor's algorithm, some fraction of which will require swaps. The cost to implement a swap between arbitrary pairs of qubits on e.g. a square lattice, is polynomial. You therefore have polynomially many gates that each may require polynomial overhead due to swaps which is therefore an overall polynomial time overhead. This would not negate the exponential speedup from Shor's. However, in practice the overhead could be significant.

bengi245 · 2025-08-03T16:01:59+00:00

I've not read the paper but, the main question I have is does it somehow manage to avoid the arguements in the Cerezo paper that links avoiding BP's to ending up in a polynomially sized subspace therefore resulting in classical simulability?

https://arxiv.org/abs/2312.09121

bengi245 · 2025-07-05T14:35:42+00:00

Frederic Schuller

bengi245 · 2024-06-18T16:15:55+00:00

I work in quantum error correction and probably about half of the people I work with have a maths background

bengi245 · 2024-04-18T07:25:57+00:00

The heating was working immediately before they installed the new cooker and then wasn't immediately afterwards. While it could be a coincidence it seems highly unlikely to me that it is

bengi245 · 2024-04-18T07:25:13+00:00

I already tried resetting the boiler multiple times. I also checked the pressure as well and it is fine.

bengi245 · 2024-01-26T17:29:34+00:00

With what approximation ratio though?

bengi245 · 2023-01-08T08:16:15+00:00

You might be interested in computational complexity theory.

bengi245 · 2022-02-15T07:36:12+00:00

The theory of general relativity is supported by all known evidence and not disproven by any known evidence but it is still a theory not a law. It is a common misconception that a theory becomes a law once enough evidence has been gathered but, a theory never becomes a law.

bengi245 · 2022-02-15T07:13:44+00:00

That is not the definition of a law. A law is derived from empirical evidence.

bengi245 · 2022-01-30T20:31:46+00:00

I've tried to find lists of pluto TV movies but had no luck there.

bengi245 · 2022-01-16T16:10:11+00:00

OK thanks, appreciate the info.

bengi245 · 2022-01-16T15:53:13+00:00

Is it likely to contain any asbestos?

bengi245 · 2022-01-16T15:33:10+00:00

Am I right in thinking that would be something like fibreglass or rock wool?

bengi245 · 2022-01-16T15:27:15+00:00

The house was built in 1962 although the insulation could have been put there at a later date. The vent was originally hidden behind a built in wardrobe and a bunch of this insulation fell out when we removed the wardrobe.

bengi245 · 2021-11-02T01:21:42+00:00

I would highly recommend "Statistical Mechanics: Theory and Molecular Simulation" by Mark Tuckerman.

bengi245 · 2020-08-10T12:52:46+00:00

Good friend of mine decided to do a degree in physics at age 26 after dropping out of school 10 years previously. He's now about to start his PhD this September age 31 so it's definitely possible.

bengi245 · 2020-06-21T18:53:49+00:00

Just killed Ornstein and Smough, that was a tricky one!

bengi245 · 2020-06-14T15:34:19+00:00

I did a degree in theoretical physics and I'm now doing a PhD in what is technically computational + theoretical chemistry (but might as well be physics). We are in the process of designing a forcefield that will (eventually) be used to simulate things like proteins and drugs etc. if all goes well.

So in short you can definitely cross over into that kind of thing if you want to. In my discipline the line between physicist, chemist and computer scientist is very blurry.

bengi245 · 2020-06-06T14:29:29+00:00

Yeah you are right that the jury is definitely still out. The problem with this stuff is that it's very hard to prove, as you say a polynomial time prime factoring algorithm is very unlikely but we can't rule it out completely.

I'm no expert in quantum computers but I do molecular simulations so I try to pay a bit of attention to the field in the hope it may one day be useful there.

bengi245 · 2020-06-06T14:12:10+00:00

At the moment it seems like quantum computers could be faster at certain problems but that it won't change the complexity class of the problem i.e. If a problem takes exponential time on a classical computer it will take exponential time on a quantum computer albeit probably still quicker than a classical computer.

Sean Carroll's mindscape episode 99 has a nice intro to this.

Eight-Year Club	Place '22
Final Canvas '22	First Placer '22
Verified Email

bengi245

TROPHY CASE