Archived threads in /sci/ - Science & Math - 1549. page

>>8191577
>Wouldn't the gravity of the more massive object combine with the gravity of the planet to make the massive object fall half a nanometer per second faster?
The "proof" people usually give for this doesn't even need to be TeXed up:
F = m1 a
F = m1 m2 G / r^2
by Newton 3 the forces must be equal so,
a = m2 G / r^2 (= g)

Which I guess makes sense in Newtonian mechanics, probably not in GR, but I don't know anything about GR so we'll wait for a physicist to pop in.

File: video-undefined-22D1E93600000578-450_636x358[1].jpg (23KB, 636x358px) Image search: [Google]

23KB, 636x358px

https://www.youtube.com/watch?v=E43-CfukEgs

see for yourself

>>8191614
This doesn't show their acceleration values measured in the nanometer scale, though.

>>8191565
I'm no chemist but we had to memorize the color of certain molecules

If I'm not wrong: permanganate __ purple.

So its a question of seeing the elements in different experiments...

>>8191565
The complexity and size of the attached molecules bend light (refraction) to generate what we see as color. Bright and vivid colors tend to be from very complexly-chained compounds. Why simple chemicals are colorless (water, air, alcohol, vinegar, etc.)

>>8191580
Continued: This also means that compounds with the exact same molecules can have a different color. This is due to a different structure. Example: if the same chemical say H10SeC5Ni had two structures. One structure was a straight line while another was in the shape of a polygon. Both would be different colors (say orange and blue). The color depends on light hitting the compound then being refracted.

OP again, I'll try to explain why I think this.

I've just completed my MSc in Psychology, and I averaged 98% in my statistics modules this year, and had similarly near-perfect scores during my BSc. So I'm some sort of stats genius right? Wrong, I'm nowhere near. Trying to deal with real data, instead of the nice datasets they give you in tests, complicates things hugely. I still have no idea what I'm doing when I try to analyse the data for my dissertation. I'm sure that I'm making shitloads of mistakes, and I keep having to try and Google answers because what I'm doing extends far beyond my course material.

That's why psychologists need to stop pretending we're capable of doing the stats ourselves (unless we study stats full-time, separately), and get proper statisticians to assist us instead. Whilst I've been studying I had to fit my stats modules in around many more psych modules, so I only have a very basic level compared to statisticians. Still, I'm technically able to be published in scientific journals (actually, data from my BSc dissertation is about to be published in EJSP). These journals are awash with research which have errors which will be obvious to statisticians, so why not just employ them full-time to improve the quality of the research? Every psychology department would benefit from this.

>>8191548
>So I'm some sort of stats genius right?
Only if you studied in Europe and not grade inflated US memeschools.

>>8191550
I'm in the UK, and did my BSc and MSc at two different Russell Group unis. Not quite Oxbridge, but Top 10. To be honest I thought that students in the US might actually be more adept at stats seeing as their courses last longer and typically have a broader focus, but that's a complete guess.

>>8191421
>sticky picture
You mean the banner contest?

In Classic Mechanics why is there no Serway and no Tipler - I used this and they are pretty good.

What are your opinions on Cohen for Quantum mechanics.

>>8191426
No for the new sticky OP (to be pinned on the front page).

The old site has many issues and deadlinks which is why we are moving towards the wiki page.

We can keep the old pic, but a lot of Anond had issues with the "timewasting" so I don't know.

>>8191433
Add them only if you think they are of significant quality, put them above or below Taylor depending on how you judge. (Physics is not my field so I couldn't tell you)

Just remember that most people reading the page are only going to take the first 1-2 recommendations, if you have more useful information add it in parenthesis ex. (good for self-study). The goal isn't to compile a list of all textbooks, but to -as far as possivle- recommend the most useful ones typically needed for a university quality education.

>>8191315
yes

>>8191350
Tell me

>>8191357
what kind of PDE? What order? Homogeneous? Lineal?

you will die in your own lifetime bro

File: xy.jpg (4MB, 2124x2676px) Image search: [Google]

4MB, 2124x2676px

>>8190848

>>8190882
Shit, man. Our own death will be the last death we will have to worry about.

Death in and of itself has become probably the biggest source of grief in our modern society.

So it's sort of ironic that all of our own pain goes away while we pass that pain on to our loved ones.

what a vicious cycle

>>8190547
Alright, I'll take the bait. What existed before?

>>8190550
I have no idea - i'm just intrigued by the idea that the universe is the result of a rip rather than an explosion. All this hypothesis implies is that beyond our known universe there must be enormous forces and more matter.

>>8190547
But the universe is expanding at an accelerated rate.

File: 1467429871579.png (66KB, 997x775px) Image search: [Google]

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>>8190021
You're a meme

How about you delete your shit thread?

>>8190021
yes because planes are much better
> meme loop can only go from A to B
> planes can go anywhere
> memeloop can go up to 700mph
> planes can go much faster
> memeloop requires a rail
> planes requires fucking air
> rails may get damaged from earthquakes and hurricanes
> planes can always avoid hurricanes
wew lad, should've invested on SpaceX, Musk.

>>8190021
yes, huge infrastructure needed (years of work and trillions of $) for a very marginal gain compared to today train (320-350 km/h), this meme wil lnever take off.

>>8189988
The primitive anaerobic cells changed the whole atmosphere adding lots of O2, making aerobic life possible.

>>8191129
And now some cells are adding a lot of CO2 to the atmosphere

>>8191939
The Great Carbonization Event has begun.

Because they're fucking depressing

This is why scientists are not in charge of social development and social planners should not aspire to "science"

>>8189927

Lower suicide rate.

>>8164190
Have you checked your bunghole?

>>8164193
wow dude nice meme

>>8164190
Nonexistent metaphysical dribble.

>>8194504
Everybody knows it's true, but poor and dumb people far outnumber the rich or the intelligent, so it's a good strategic move as a politician to bone the latter two and get the vote of the former two.

How German schooling works:

http://www.ukgermanconnection.org/german-school-system

According to talent regarding intelligence and/or school performance as a child you are put into a certain level of schooling. The less intelligent students take much less schooling and are immediately put into the workforce. Average-talented get slightly more schooling. The highly talented receive much more schooling.

>1) Hauptschule
In the majority of the federal states, students spend five years at the Hauptschule. The main objective of the Hauptschule is to prepare students for their entry into the world of work. Once students have obtained their Hauptschulabschluss (leaving certificate) at the age of 15-16, they can go into vocational training, start entry-level work in the public sector, or attend a Berufsfachschule (full-time vocational school).

>2) Realschule
Students attend the Realschule for 6 years. It gives them a broader general education and expects them to show greater independence. In comparison with the Gymnasium, the pupils are given a more vocationally-oriented education. At the end of Klasse 10 they obtain the Realschulabschluss (leaving certificate), which gives them different options: in-company vocational training, work in the public sector at entry and executive level, or further school-level education at secondary level II or at a Fachhochschule.

>3) Gymnasium
Students attend the Gymnasium for eight or nine years before they take their final examination (Abitur or Hochschulreife). The Gymnasium is designed to provide students with an education which will enable them, once they have passed their Abitur, to study at a German university or equivalent. Students at secondary level II (the last two or three years at the Gymnasium) select two or three Leistungskurse (specialist subjects). Their Abitur mark is based on the assessment of these Leistungskurse and two other subjects.

Wasting time and money of less intelligent people by tricking them into studying while they are not capable of taking significant advantages of it is pretty much scam.

>>8189302
Physicists are just applying what they learnt in sixth grade algebra.

1 + x = 3

well, clearly 1 is not equal 3, so just assume that the weird x symbol that nobody really understands or even knows what it is represents 2 dark numbers and then you plug in

1 + 2 = 3

Therefore, that x must indeed be 2 dark numbers because it makes our equations make sense.

What? Circular reasoning you say? That cannot be it, I read a book that said that this is not circular reasoning and you can trust the book because I support it and think it is absolute truth.

>This is what happens when physicists are not forced to take logic and other rigorous mathematics courses

>>8189325
Numbers don't lie. And just because you don't know what something is, doesn't mean you can't name it.

Calling the variable "dark energy" is much more interesting than just "x".

>>8189302

You forgot the part where the geometry of our universe has been experimentally verified as being flat.

However, a flat universe would require a gravitational every equal to 0.

Which is defined as omega = 1.

Calculations of all the matter in our universe gives us a reading of omega = 0.3, which would indicate an open universe.

The universe is also expanding faster than it should be, given that reading.

In addition to this, what we refer to as empty space has been experimentally observed to be full of energy, in the form of virtual particles and fields popping in and out of existence.

To return to omega = 0.3 clashing with the measured curvature of our universe:

If you put 70% of the energy of a flat universe into empty space, then you get omega = 1.

Therefore: dark energy.

>>8193598
If a sequence is infinite and is not repeating, by definition it contains all possible finite sequences

>>8193600
How do we know a sequence doesn't repeat

Also I guess what stops it from going on forever without ever containing a specific subsequence ? How do we KNOW

Necessary bump

>>8193491
Depends what you mean by understand.
You can look up the definition and basic properties with no prerequisites at all.

>>8193491

next to none

But you need math to be a good programmer