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Devac's profile

I'm a mathematics and physics student, which summarises many of my interests ;). In addition, I'm an avid fan of metal and RPGs (Role Playing Games).

Some extra stuff you might need to know about me:

I'm half-Polish and half-German, know the Polish language much better than German, but I can get at least the gist of it. Other than that I know bare-bones Czech and Swedish. For the sake of completeness, I also know English. ;)

I'm dyslexic and colour blind (the red-green type), that's to excuse miscommunication and me calling something eye-straining or unreadable. It's a rather extreme case of the bottom left in this picture.

It's not uncommon for me to call pounds, ounces and similar non-SI units of measurement as Wizard Units (WU). That's not due to hate, but it does feel annoying when most people in the USA or the UK can't be bothered to convert them on their own. Yet, moan whenever I would confuse some Pennsylvanian Liquid Ounce with Imperial Lager Ounce. I'm not even certain if the units I made up there are not real! It's a miracle you don't have TI-81 Shaftment to measure distance.

I don't like people making poorly reasoned accusations about me. If you think that you can give me a lesson on something give me a god-damned lesson instead of calling me names.

I don't have any problems with personal beliefs. It includes but is not limited to sexual orientation, gender issues and food choices, and all that other crap. I honest to whatever you find holy/unholy/other don't care. Just don't try to evangelise at me. That's among the easiest reasons for me to block/mute someone, beforehand calling them a sanctimonious git.

If you think that I'm disrespecting you: please, assume that I had a really bad day. I don't think I'm violent by nature. I think that I'm neither offensive nor a douche. But when I'm not at my usual laid-back state I will jump to HULK SMASH in an instant. And usually switch back as fast. Yes, I am serious.

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comments 50

If I didn't fuck it up, it should total to 4613085 (which is slightly less than the high estimate they got). But the data in the Reddit-linked spreadsheet seem to be changing. For instance, you have a value of 1500 for Gainesville (FL) while in the spreadsheet both the low and high estimates are 1000.

I would wait with estimates for a while longer. They still have a disparity that's about 1.3 million between the low and high estimate. And when the midpoint is about 4 million… that's a margin of error of (4.0 plus/minus 0.65) Megapeople ;).

See? It's getting at least that much better.

    But it seems to me that even foreign countries have a stake in the outcome of the news.

So… when you can't feel like you can trust anyone, why even track the news? Yeah, it could be possible that external news sources would skew the picture or report something fake, why not. But it would be a hell of an accomplishment to get all of the UK/EU outlets to report the same version despite their differing leanings. And if you would not trust someone who would go through the external news to report on their quality, you would have to do it yourself. Why trust Snopes for that matter? Visit White House archives and check for yourself. Don't trust archive.org? I don't know what to say.

In the end, you have to either trust someone or be best served by ignoring all the news. For what it's worth, I'm willing to trust BBC despite the fact that the moment I think of England (well, at least the people I had the displeasure to interact with while I was there) I want to punch someone. It's your call in the end.

Devac  ·  link  ·  parent  ·  post: Grubski Challenge : Steak

Damn it! I finished eating mine less than half an hour before you posted this. Oh, well. I guess I'll have to cook another one tomorrow. :D

Do fish stakes count as stakes?

It's hardly a good solution, but perhaps application of independant source tracking and outside news sources could help? BBC US & Canada section strikes me as a fairly good option. Hell, I would not be surprised if you would have a Soviet reversal of sorts and find yourself getting better news from Canada or Europe. I'm not trying to imply that somehow their journalism is better (I'm neutral on the subject), but simply because they don't care about some minor districts or case and focus on larger events it's at least filtered.

Just a suggestion.

Devac  ·  link  ·  parent  ·  post: Pubski: January 18, 2017

OK, sorry for the delay but I was fucking drained after three exams in one day. Aside from a few bits that I got wrong (actual date for the first MM Experiment: 1887), I hope that you got the gist. But to avoid using aether theory as what needed to be disproved, let's look into the postulates of special relativity.

1. The principle of relativity.

2. Invariance of the speed of light.

3. Invariance of the electron charge.

The principle of relativity is, in a way, an extension of the Newton's First Law of Mechanics "in an inertial frame of reference an object is immobile or moving with a constant velocity unless acted upon by the external force". In the case of the special relativity, it takes a more general form of "the laws of physics will stay the same regardless in all inertial frames of reference; any frame of reference will not change its state unless the transformation that acts upon it isn't a translation".

Newton made his postulate in regard to any object within the inertial frame of reference. Einstein generalised it to the whole frames of reference by showing how a translated frame (or a one moving with a constant velocity) will be indistinguishable from the static frame. How does the mathematics of it look? It's just a physical interpretation of an affine space. The proper translation of an affine space == relativistic inertial frame of reference.

Invariance of the speed of light is a bit tricky, but it can be best explained by taking a distance in one frame of reference X = sqrt((x - x_0)² + (y - y_0)² + (z - z_0)²) = c(t - t_0) and looking at its affine translation. What will be X'. It's called a spacetime interval by the way, and if you have looked at the Minkowski's diagram page that I linked before it should start to get clear after plotting distances and moving them around. I don't know if that's the type of 'physical' reasoning that you wanted, but it was a consequence of binding time and space into the spacetime where the change of distance is linked to change in… time. The speed of light is a constant for sake of affine transforms of the spacetime. And when compounded with the principle of relativity we have no reason to think that something would add to it, even if the frame itself is moving. Proof? Michelson–Morley experiment.

Invariance of the electric charge… hm. Let's just say that it makes sense when you take the Maxwell's Equations and perform the same affine maths on them and the continuity equation. :D

By the way, while I was writing this some of my grades got updated on the student server. Guess who's grade are the same as his blood type: A(Rh)+ :P

EDIT: By the way, feel free to ask some follow-up questions. I'm not going to deny that I was groggy as fuck while writing this explanation so it's almost certain that I wasn't all that clear at places.

Devac  ·  link  ·  parent  ·  post: Pubski: January 18, 2017

    do we have any more motivation for Einstein's special relativity postulates other than "it makes sense and, seriously, what other way would you try to formalize reality?"

Yes. I can write you more, but later. I have my first exam in literally two hours, so it needs to wait until… uh. Roughly your morning in about ten hours? In the meantime, I feel like you should know that physics was quite different back in the time of Einstein's early work. It was all due to luminiferous aether.

In 1902, about three years before Einstein's paper, there was an experiment performed that fundamentally changed how we should approach aether. And even ask if there is supposed to be any aether. It was actually quite astounding change, some of my lecturers compared it to confirming the existence of Higgs boson as there are many formulations of Standard Model that worked perfectly fine without it. We now know that they are false or, at the very least, flawed. Same thing happened to aether because of the Michelson–Morley experiment.

Seriously, read about aether. And if you don't want to… it was basically a mainstream physics equivalent of the fucking Force from Star Wars. You know, "Its energy surrounds us and binds us. Luminous beings are we, not this crude matter. You must feel the Force around you; here, between you, me, the tree, the rock, everywhere, yes. Even between the land and the ship." <- that's a surprisingly apt description. It was separate from matter, filled all space (even the space occupied by matter itself) and could only be interacted with by the particles that possessed an arcane quality. The Electric Charge. :D

Anyway, gotta go. If you would want me to explain more, I will be happy to do so but I seriously need to go.

EDIT: Actually a better link to aether is the Lorentz aether theory as it was the place where Einstein started his work by and large.

    It's all good man, this semester will be a much more pleasant experience, it looks like.

I fucking hope so! It would be hard to get worse for what I know.


Huh. I'll look into it a bit more. Although as far as access to publications goes my university seems very generous with granting it. But seeing how the last time the download speeds were in dial-up tier… I will not deny that I have been using services like sci-hub despite having legal access. It's just so much faster!

Either way, I'll look more into it.

    I'm interested to know if you're leaning in the direction of a particular discipline yet.

Allow me to say it like this: there's a good reason why the ratio of theoreticians to experimental physicists at my uni is around 3 to 1. Laboratories and anal-retentive grading (point deduction for such grievous offence as misusing the holy sheriff font) combined with ludicrous (comparatively) deadlines don't really endear anyone from my year to go the EP route. Before this semester I had no idea that something can make lasers boring.

I'm unlikely to improve the ratio, although I'm not sure in what type of theory I would like to specialise. I think that I'll get more thought to it after the upcoming semester. Either way, BSc isn't a specialised degree. You get a specialisation as a post-grad. Bit weird but our undergrad is only three years. Most of it is about getting us up to speed with what was fresh in 1940's. ;)

Specialisation in mathematics is a much simpler choice. Applied mathematics, likely some branch of analysis (ODE, PDE, dynamical systems, control theory… that sort of thing). I enjoy it all while completing all related courses (at least so far) without breaking the proverbial sweat.

EDIT: Oh, one more thing about labs. It's largely out of sync with our theoretical classes sans the General Physics series of courses (I: Mechanics, II: Electricity and Magnetism, III: Vibrations and Waves, IV: Optics) as those come with an associated two hours long laboratory. So for this semester, we had to read about shit like Einstein's Coefficients while having little to none of the formal backgrounds in quantum mechanics, statistical physics or actual optics. I would much rather have only the labs from General Physics courses and then have one lab during the senior year that would consist of:

- lasers,

- basic condensed matter physics,

- radiometry,

- fiberoptics,

- atomic and nuclear physics,

- particle physics,

and so on. I can dig a year-long course that consists of seven or eight experiments.

But if the graduate level laboratories are similar to the ones we have now, ahead of schedule just for the sake of it and cramming 12-14 experiments into 15 weeks of semester… yeah. I would much rather specialise in QFT as a yet another theorist than going through three more years of labs like the ones I have currently. I'm actually writing a motion to the dean about that, as I can't believe that I have a better idea than people who made our degree curriculum after giving it fewer than ten hours of thought.

Devac  ·  link  ·  parent  ·  post: Pubski: January 18, 2017

Well, special relativity can be treated with a surprisingly little maths so I wouldn't get too excited about that part. I don't know about your course in particular so excuse me if I'm wrongly whetting your appetite. For me, it was much, much, more about understanding time-space relations on Minkowski's diagrams and knowing in what frame of reference you work on than doing anything more complex than a change of base maths-wise. Most of the problems that can cause you a major brainfart don't even require calculus. :D

First three lectures in this series will likely cover a lot of the basics for you if you would happen to need some revision. Basically, the Susskind's website as a whole (home page) is a really good resource for that. On that note, I can offer you some help if need be.

Devac  ·  link  ·  parent  ·  post: Pubski: January 18, 2017

What was the example? What is the course about?


That's honestly all I can say regarding your workload. And likely-cheating students. And material. And workload again, purely because it deserves it. Just… damn.

    Are you on ResearchGate yet?

Should I be there at all? I'm not doing any research that's worthy of publishing or reading about.

I got the response about CSH - ETCS comparison, she actually wanted to talk about it in person after looking me up in student registry. I'm pinned as a possible exchange candidate and her reasoning was that I would want either more tips or some sort of recommendation. Anyway, here are some key points from ou talk:

Conversion is difficult because here it is largely assumed that courses take more hours with lecturer and TA but will require fewer hours of student's individual effort. I've described it here to clarify how it looks in Poland to am_Unition. Homework is almost exclusively a follow-up from where we have left in class.

Let's say for example that we would have a problem about ballistics. Point a) would be to describe the starting conditions, point b) would be about finding the required conserved properties and discussion of why we can treat something as such. Point c) would be about describing the trajectory, finding out some interesting properties of our findings. Homework would be doing the same for a case where, for example, we would assume that the drag isn't proportional to velocity but to velocity². It's a marginally different method of getting to the solution, but the end result would be different enough to prompt 20--30 minutes worth of discussion in class. We are also big on giving students 'gotcha!' assignments where it's pretty much expected that everyone will get the wrong result. That's why the discussion isn't just "everyone got x(t) = some function? Good! Now to the matter at hand…" but something that takes a while longer. You learn better of off your failures etc. You can get it counted as an extra credit if you can disprove the TA's solution or find a better one by the way. That's to encourage independent research. Group effort is also welcome. For classes like the mentioned by me Vibrations and Waves, we can even request additional lab access to gather data for such attempts. Since, you know, experiment decides if the theory is correct or not.

However, I have to say that my initial assumption was wrong. According to the mentioned post-doc, I'm completing a rough equivalent of 29-33 course hours. To me, that's just a bit more than what I'm expected to complete for a double major. I don't know what to say. I don't feel like it's too hard, but perhaps there's indeed some truth to people telling me that I'm some sort of prodigy, at least in the mental stamina department. I definitely don't feel like one. Truth be told, I know people at my uni who are leaps and bounds ahead of me and truly deserve to be called geniuses. Hell, I feel like a complete moron when compared to a girl that, for god knows what reason, wants my input and opinion about her research assignment. Either I'm literally surrounded by superhumans that skew my view or I simply can't judge workloads.

Sorry for a lengthy post, but I hope that it was at least somewhat helpful. I sure hope that it brought some light to how our studies differ. ;)

Oh, as sorry for grammar. This whole post just reads wonky to me.

Devac  ·  link  ·  parent  ·  post: Pubski: January 18, 2017

I got an idea about moving forward my research assignment! I've been stuck in place since November but, barely two days after I threw away my notes and decided to start anew, it clicked in my head. After applying the TTMMP (There are Too Many Moving Parts) technique I have succeeded in decomposing my problem into a bunch of smaller, completely separate, cases.

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