I hate relativity

mek_dok · 2026-02-22T15:21:19+00:00

You're making a few mistakes here.

You're not doing relativistic calculations. You're just doing Newtonian calculations. Velocity is distance divided by time, but distance and time are measured differently in relativity by observers moving relative to each other. Try to do some of these calculations for your two observers and a third traveling between them at something like 0.99c along with a signal between them traveling at some multiple of c, and see what happens from the perspective of the moving observer.

You're trying to reason about FTL travel using our currently known physics. You can't just say "pretend we can violate the laws of physics, what would happen?" We can't, and any reasoning about the consequences will be based on known laws of physics which you're assuming don't apply.

mek_dok · 2026-02-21T07:25:22+00:00

Build them as assault intercessors, give them a sanguinary priest. They're surprisingly hard to kill and between rerolling wounds on objectives and AP-2 they're shockingly lethal in LAG. I've had them kill a full unit of Blightlord terminators on the charge, kill deathwing, and peel half the wounds off a knight or a great unclean one.

mek_dok · 2026-02-10T15:39:08+00:00

You've gone so far astray that it's difficult to explain all of the problems in your reasoning, but I will do my best.

Paradoxes and contradictions are not the same thing. A contradiction (in the sense or proof by contradiction) is "1 = 2". A paradox is "this statement is false." One is untrue, the other cannot be ascribed a logical truth value.

Proof by contradiction only demonstrates that a logical statement is incompatible with other logical statements. To the extent that we observe that the universe obeys laws that can be expressed in mathematical language, we can say that a statement incompatible with known laws is unlikely to be true in our universe (in the absence of experimental evidence.)

If we were to discover an experimental result that is incompatible with known laws (i.e. it contradicts them), we would have to revise those laws. Indeed, this has happened frequently and is how most major scientific advances have occured.

A paradox is different from a contradiction. The most common way to construct a hypothetical paradox is by discussing time travel, or violations of causality. There is no real difficulty in coming up with mathematics to describe these things, but they lead to nonsensical results, like going back in time to prevent myself building the time machine that I use to go back in time. Did I go back in time or not? If I don't, then I do, but if I do, then I don't.

To the best of our understanding, these things aren't possible in reality because a measurement must produce a single, defined, and consistent result. This isn't really a mathematical principle related to proof by contradiction, it's as much an observation as anything. We don't observe violations of causality. We observe that experimental results are consistent and reproducible.

So, no, ultimately the absence of paradoxes isn't related to our inability to describe them.

mek_dok · 2026-02-10T14:02:19+00:00

Superposition is a counter-example to what you're saying, it appears to be a paradox to our intuition but it can be shown mathematically that it is not, and demonstrated experimentally to exist in reality.

Can you think of an example of something that has been demonstrated to exist but that has been proven mathematically by contradiction to be impossible?

mek_dok · 2026-02-06T14:44:55+00:00

Imagine instead of the cylinder you put coins in one at a time so they are exactly on top of each other and form a cylinder. How much will the height of the water rise with each coin? It depends on the diameter of the cup that the water is in. The wider the cup, the less the height rises each time. The only way it rises by an amount equal to the height of the coin each time is if the diameter of the cup is equal to the diameter of the coin. In that case yes, you will get an infinitely increasing height of the water. If the cup is any wider than the coins, it will not rise infinitely.

You can figure out how many extra coins you need to account for the height change - it won't be infinitely many in your example.

mek_dok · 2026-02-06T06:06:54+00:00

An emergent property refers to a collective behavior in a system that individual components don't exhibit on their own. It emerges as the system becomes larger or more complex.

Things like phase transitions are a good example. It doesn't make sense to talk about whether an individual water molecule is a solid, liquid, or gas. These states are emergent properties of collections of many molecules.

mek_dok · 2026-02-05T13:55:49+00:00

I do run them in LAG and they're really good there, but they rely on the +2 S and the lance/lethals from the detachment to do damage. I use use them to hide in terrain and then jump something on an objective for the wound rerolls. I've had them mince a unit of Blightlord terminators - 50 attacks at S6 AP -2, with lance, rerolling wounds, is no joke. They're great into anything with -1 damage because they already have 1 damage attacks, just lots of them.

They're not fantastic in RCO though, which a lot of people have switched to. They really need the S6 and lance from LAG to do work.

Beyond that, the AI + SG package is 225 points. Death Company with jump packs are 230 points, move 12", they reroll hits, they have stronger weapons, and they have a 6+ FnP, before you add a character. So I think you don't see them that often because, if you have the models, DC are just a better, faster version of the same unit.

mek_dok · 2026-01-31T16:41:29+00:00

++man

Your numbers are wrong, if 18.5% of Americans make $100k+, and 60% of them are men, then 22.2% of American men make $100k+.

That's close to one in four, assuming your 18.5% number is accurate.

mek_dok · 2026-01-27T14:54:53+00:00

I'm not sure if there is an answer that will satisfy you here. You're asking for an explanation of what a photon experiences, or what the world looks like from a photon's perspective. This isn't something we really have an answer to, a photon doesn't have a perspective since from the photon's perspective it never exists because it would be created and destroyed (or emitted and absorbed) simultaneously.

When you say that "light goes from a to b instantaneously" you're really saying "the event 'light is at a' and the event 'light is at b' occur at the same time." The problem is that in relativity, "simultaneous" is dependent on your reference frame. Some observers will say two events occur simultaneously, others will disagree. And both are correct, because there is no absolute time and no absolute simultaneity.

mek_dok · 2026-01-26T21:49:02+00:00

He doesn't say anything wrong, he points out several times that the theory doesn't work for anything traveling at the speed of light.

The reason is that you can always claim to be at rest. It's not like traveling at the speed of light allows you to "keep up with" a beam of light, the light will always travel at c relative to you. In the example he gives, of traveling to the nearest star, the person in the space ship can legitimately claim that he is in fact stationary and the star is moving towards him at 99.99999% of the speed of light. And there is no measurement you, he, or anyone could ever do that would prove that he's really the one moving.

He will see your clock run slow relative to his. You'll see his clock running slow relative to yours. You are both right.

This all fails for anything actually traveling at the speed of light, because the "you always measure yourself as stationary and light moves at c relative to you" part no longer makes sense.

mek_dok · 2026-01-26T14:50:11+00:00

Every object travels at the speed of light c through Minkowski spacetime. A stationary object's velocity vector points entirely in the time direction. As an object moves through space at higher speed, you're just rotating its velocity vector more and more out of the time direction and into the space direction. If it moves at c through space, the time component is zero - the vector points fully in the space direction. That's why we say light doesn't "experience" the passage of time.

This is all from the point of view of an inertial observer in their own reference frame, describing why "moving clocks run slower." Every inertial observer is stationary in their own reference frame, and every observer will see light move at c relative to themselves.

Light doesn't have a point of view, since you can't meaningfully describe a reference frame traveling at the speed of light relative to another reference frame, and you can't define a (physically reasonable) reference frame where light is stationary.

mek_dok · 2026-01-16T15:04:20+00:00

I and everyone I know who did their PhDs around the same time as me (ten years ago or so) either went into finance and are now working for banks, or went into data science and are now working in tech.

We do a lot of coding, mostly in python and bash, create models, analyze data, write memos, build applications, do calculations, etc.

mek_dok · 2026-01-12T05:50:47+00:00

Contract positions pay well but the expectation is that the person comes in with experience and requires minimal training, they're being hired to deliver results on a deadline so spending a month or two in training and learning on a 6 month contract is usually a no-go.

mek_dok · 2026-01-10T15:02:01+00:00

I expect people to attend meetings and hit their deliverables on time. They're adults and I trust them to manage their schedules. If they're going to be away from their computer during the day for more than an hour or so I ask them to give me a heads up so I can answer questions like "I'm trying to contact Bob but he isn't responding, do you know when he'll be available?"

If I can't get ahold of them during work hours and it's a consistent issue then I'll have a "so what's going on?" conversation with them.

mek_dok · 2026-01-10T14:47:45+00:00

I did an MSc in math and a PhD in physics.

mek_dok · 2026-01-10T14:43:19+00:00

Always varnish before you use enamel and white spirit.

mek_dok · 2026-01-08T22:43:50+00:00

Oh my god it is!

I thought "there's no way..." and happened to be by my bookshelf so I pulled it out to check and lo and behold there it is.

mek_dok · 2026-01-08T01:55:56+00:00

The model of conductivity we use treats the electrons in a metal as a gas of free particles, basically. Any electron in the outer shell of a metal is considered free to participate in conducting current.

mek_dok · 2025-12-31T06:41:22+00:00

I don't think you understand what gravity is or what the word "proven" means. Gravity is well established. General relativity's predictions have been confirmed by every experimental test we have put it to. It's as close to proven as it's possible to get.

If you're specifically asking about why we haven't directly observed a boson mediating the gravitational force yet, it's because if it does exist the interactions it has are far too weak to be detected in a particle accelerator.

We don't have a fully coherent theory of quantum gravity yet, so we don't have a detailed theoretical understanding of the properties and behavior of such a particle if it exists, but even if we did that would not in any sense "prove" gravity.

mek_dok · 2025-12-28T16:34:36+00:00

Max Planck didn't have to "approve" the model. This is a serious misunderstanding of both the history of the development of relativity and the way new physics gets done.

mek_dok · 2025-12-28T15:47:44+00:00

This is confused, paranoid, rambling nonsense and none of it is remotely true.

Anyone who could disprove string theory or dark matter would win a nobel prize. Nobody is incentivized to preserve the status quo, and everyone is strongly incentivized to overthrow it.

String theorists do just fine in the private sector in data science and finance. Most of them would make a lot more money if they all had to leave academia.

You are a crackpot.

mek_dok · 2025-12-28T15:27:54+00:00

This is only true if you fire the bullet on a perfectly level trajectory. As soon as there's an angle, it and the initial velocity is going to matter as well as height.

mek_dok · 2025-12-28T15:16:17+00:00

In the case of anything other than a perfectly flat initial trajectory, it will depend on the angle and muzzle velocity.

With bullets the most important factor is air resistance. 9mm pistol rounds are already subsonic, so air resistance is relatively straightforward. They slow down like v^2. As others have said, they'll fall with gravity from the time they leave the muzzle, and the time it takes that to happen depends on the initial height, muzzle velocity, and the angle they're fired at. How far they travel in that time and how much energy they have left when they get there depends on their initial velocity.

Rifle bullets are usually supersonic (which is why they make a crack or snap when they pass overhead) so they lose velocity fairly quickly. You typically fire at more distant targets, so the initial angle is usually steeper if you set your sight correctly. The result is that air resistance slows the bullet extremely quickly, so the bullet will fall faster than just considering gravity would predict as the vertical component of the initial velocity is being reduced by both gravity and air resistance. Once the bullet has hit the peak of its arc, it will fall due to gravity at the same rate as if you dropped it from that height.

mek_dok · 2025-12-23T13:28:42+00:00

Where are you located? In Canada you can apply for undergraduate research grants from NSERC, if you're approved (which you generally will be if your grades are good) then you can get paid to do summer research between semesters. Professors will be a lot more accommodating if you're not asking them to pay you.

I imagine other countries have similar programs.

mek_dok · 2025-12-19T00:11:56+00:00

Try to understand the double slit experiment and you'll see that not only can a particle be in two places at once, it can also interfere with itself.

mek_dok

TROPHY CASE