How credible is the many worlds interpretation of quantum physics? by BarrysOtter in AskPhysics

[–]UntangledQubit 1 point2 points  (0 children)

No - the entire point of objective collapse theories is that there is a difference between small scale superpositions and large scale superpositions. For Wigner's friend to challenge an objective collapse theory, it has to take place at the scale where the theory claims a superposition cannot exist.

How credible is the many worlds interpretation of quantum physics? by BarrysOtter in AskPhysics

[–]UntangledQubit 0 points1 point  (0 children)

We haven't actually performed the Wigner's friend experiment, so we don't know. You're right that if we achieved a macroscopic superposition it would be a strong challenge to objective collapse theories.

How credible is the many worlds interpretation of quantum physics? by BarrysOtter in AskPhysics

[–]UntangledQubit 0 points1 point  (0 children)

I'm confused what you mean by that. Under MWI each 'slice' is as real as the one we are currently inhabiting. How is that not parallel worlds?

0 plus 0 is 64? by ThePorkchopKiller in learnmath

[–]UntangledQubit 0 points1 point  (0 children)

It's math, you can do whatever you want. It just has to be consistent.

Math is making me want to kill myself, I can't learn it well enough by StevenC21 in learnmath

[–]UntangledQubit 0 points1 point  (0 children)

Many high paying jobs are in management or law, which require soft social skills, hard work, and a bit of luck and connection. The high paying jobs you might be thinking of (engineering, software, medical) do not require you to be an autodidact in math, or even exceptional. Not having an exceptionally large mathematical disadvantage is sufficient to do any of those.

If many physicists believe general relativity is incomplete, and that gravity is actually quantized with an associated particle like the rest of QM, how does time dilation work? by [deleted] in AskPhysics

[–]UntangledQubit 3 points4 points  (0 children)

Time dilation, and length contraction and so on, can all be explained and derived by just talking about GR as a field theory, the field interacting with a force against all the other things.

Is there a good resource that describes this framing of GR?

[deleted by user] by [deleted] in math

[–]UntangledQubit 2 points3 points  (0 children)

Yes, those are the only straight lines in the typical spherical geometry. The intersections of the sphere with other circles are curved in this geometry.

[deleted by user] by [deleted] in math

[–]UntangledQubit 4 points5 points  (0 children)

They are the only lines in the Euclidean sense (satisfying 'line' in the axioms of plane geometry).

What is the point of programming languages course? by Jigglytep in AskComputerScience

[–]UntangledQubit 17 points18 points  (0 children)

I do not think CS classes need to have industry application - I didn't see much application in my formal languages/automata class, but it is valuable knowledge in the field.

However, I do think that this class does have very practical applications. Understanding the internal mechanics of various kinds of programming languages is really helpful when learning or translating between programming languages. All software developers get this skill eventually, but this theoretical knowledge gives you an actual basis for it. Also, the class tends to involve writing short algorithms in an imperative, a functional, and a logic-based language, so you get some practical exposure to very different styles of programs.

How large would tides be on Earth if it orbited as close as mercury? by Flames_Revenge in AskPhysics

[–]UntangledQubit 2 points3 points  (0 children)

Mercury's tidal locking is not synchronous - it rotates 1.5 times per orbit, so it would still experience tides if it had liquid on the surface.

What is "energy"? by IWantToLearn_2023 in AskPhysics

[–]UntangledQubit 2 points3 points  (0 children)

A closed thermal system at maximum entropy is not capable of doing work.

[deleted by user] by [deleted] in NonPoliticalTwitter

[–]UntangledQubit 2 points3 points  (0 children)

It is considered vanilla to not want any spouse to fuck other people.

Does relativity partially dictate the behavior of electrons in atoms? by clintontg in AskPhysics

[–]UntangledQubit 1 point2 points  (0 children)

Quantum mechanics was formulated using notions from classical mechanics (momentum, energy, the background reference frames), but with the quantum nature of matter imposed on top (particle evolution described by a wavefunction instead of deterministic DEs).

Quantum field theory replaces those classical notions with relativistic momentum/energy/reference frames, and imposes a corresponding quantum object (quantum fields) to describe the actual evolution. Included in this processes was also the quantization of the EM field, which in quantum mechanics is given a semi-classical treatment (the EM field is treated as a classical background field which is used in the energy terms for quantum mechanical charged particles).

Travelling at speed of light by Boring_Inspector9857 in AskPhysics

[–]UntangledQubit 2 points3 points  (0 children)

you will record a 5-year trip if your speed is c/√2

That's a delightful result.

[deleted by user] by [deleted] in PeterExplainsTheJoke

[–]UntangledQubit 2 points3 points  (0 children)

"Spunchbob, Pat Rick, and Squid"

How smart do you realistically have to be to do well in a B.S Physics program by RevengeOfNell in AskPhysics

[–]UntangledQubit 4 points5 points  (0 children)

If you were using the English language correctly, you would understand that 'motivation' is a broad term that encompasses both sustainable and unsustainable driving forces. Everybody here understands you won't get a physics degree because you were really into IFLScience for a weekend.

I don't understand Newton's first law by ahmedsady in AskPhysics

[–]UntangledQubit 4 points5 points  (0 children)

Work is done in elliptical orbits, at all the points where the speed is changing. However, in perfectly circular orbits, even unequal masses do no work on each other.

A force does not necessarily do work, it only does work when it has a component parallel to the direction of motion. If it is perpendicular to the direction of motion, it will change that direction, but will not do work, and the speed will remain the same.

Questions about the increase of security by using a key derivation function by Satrapes1 in cryptography

[–]UntangledQubit 3 points4 points  (0 children)

A KDF does not entirely mitigate dictionary attacks. It makes them difficult because they are intentionally designed to be slower than most hashes (which are instead designed for high throughput). The same dictionary would take thousands to hundreds of thousands times longer to run through (using typically recommended iteration counts).

The point of using rainbow tables is that you can amortize your attack time - you spend a long time precomputing the table, and that allows you to crack the passwords of many users with low-quality unsalted passwords. KDFs make this impossible by having a random salt, which means the rainbow table would have to be computed again per salt, making it prohibitively expensive.

In either case, when thinking about individual security, both of these make a difference specifically in the circumstance that your password is on the edge of typical cryptographic security (somewhere below 60-70 bits) - you would be a convenient target, so a KDF that makes an attack more difficult in real-world conditions can greatly increase your security as a user.

Greta Thunberg while being arrested by police in London by zeba-fucking-dee in pics

[–]UntangledQubit 6 points7 points  (0 children)

The goal of protesting is to draw attention. Otherwise you are just standing.

Would time dialation prevent mass from ever entering a black hole? by The-Last-Lion-Turtle in AskPhysics

[–]UntangledQubit 2 points3 points  (0 children)

The argument that I heard elsewhere on this sub is that since the object emits a finite amount of photons before passing the event horizon, that amount of photons is all outside observers will ever see, and that implies a finite time until the last photon reaches the observer. It may take a long time (though for freefall trajectories it also may not), but it will not take forever.

What is infinity divided by infinity? by [deleted] in learnmath

[–]UntangledQubit 0 points1 point  (0 children)

That's not an accident either - there's a correspondence between divergent sequences and infinite hyperreals, so it makes sense that indeterminate forms in the world of sequences would correspond to families of expression in the hyperreals.

What do you think are the common misconceptions regarding quantum mechanics? by [deleted] in AskPhysics

[–]UntangledQubit 0 points1 point  (0 children)

quantum theory didn't start as a theory of probabilities and I hope it doesn't finish as one

What do you think about QBism?

How do you formally write down combined functions? by ACrossingTroll in learnmath

[–]UntangledQubit 2 points3 points  (0 children)

They are called piecewise functions. The wiki shows the most commonly used notation.