31

Flat Earth Debate / Re: Perceptual Argument for FET in Premise Form

« on: November 27, 2009, 04:27:03 PM »

many other people who conducted that experiment had different results. why are their findings less worthy?

No one got different results.

i got different results

32

Flat Earth Debate / Re: Perceptual Argument for FET in Premise Form

« on: November 27, 2009, 03:01:56 AM »

many other people who conducted that experiment had different results. why are their findings less worthy?

33

Technology, Science & Alt Science / Re: Occam's Razor

« on: November 24, 2009, 03:13:28 PM »

i think there's no point in debating here as tom just defines the true answer as the simplest explanation. that way occam's razor will always be correc. however this implies knowing the correct answer which makes occam quite useless. the point is this reasoning only works in retrospect and there's a fair chance that the different models switched their roles concearning simplicity during the process. so models that didn't seem to be simple in first place (and are not favoured by occam at that stage) might prove to be the correct ones (you might want to say the simple ones)  after further investigation. but when you reach that point there's no need for occam at that stage.

34

Flat Earth Debate / Re: Itchy's moonlight study.

« on: November 15, 2009, 01:42:27 PM »

ok, good luck 

35

Flat Earth Debate / Re: Itchy's moonlight study.

« on: November 14, 2009, 10:00:30 AM »

i'm not sure if it really fits in here

could you repeat your experiment for a third time using some sort of artificial light instead of moonlight? in my opinion you have proven that exposion to light during sleep is "harmful", you should check if artificial light (as sunlight isn't available) has the same, different or no effects.

36

Philosophy, Religion & Society / Re: A question for Europeans

« on: October 11, 2009, 09:05:08 AM »

I know In germany there are some crazy anti immigration idiots that want to kick all the turks out.

you can find them in almost every european country. but i admit that there are still way too much of them in germany. austria is worse when it comes to anti semitism. a lot of people in france are against immigration from africa, same with italy and spain.

37

Arts & Entertainment / Re: The latest xkcd

« on: September 30, 2009, 05:13:34 AM »

made me laugh:

alt text: "More generally, with great power comes great dEnergy/dt" 

38

Flat Earth Debate / Re: Color Shift on stars

« on: September 25, 2009, 04:32:21 PM »

ok, thanks. i never heard of it before and it really caught my attention now. if it holds true it would change our view of the universe especially regarding distances quite a lot.

39

Flat Earth Debate / Re: Color Shift on stars

« on: September 25, 2009, 03:49:34 PM »

What about dispersive extinction?

i just read the paper and it is quite interesting. i don't like the possibility of a static universe as it creates other problems but i guess this theory could also work with an expanding universe.  the authors proposed quite a simple experiment to test their theory, do you know whether these experiments have been conducted?

40

The Lounge / Re: Today, in my physics lab

« on: September 24, 2009, 07:58:29 AM »

It mentions how to properly calculate errors for a given function of a measured variable in the appendix of our lab manual, but it isn't particularly clear on how to go about using the equation given, and there are no examples of its use beyond the basic addition, multiplication and index rules. I actually don't know, for instance, how to correctly transform an error in x into an error in, say, log x, or tan x. I wish I did, but unfortunately I don't. Maybe I should look it up on the internet.

a book that helped me a lot is "An introduction to error analysis" by Taylor. i have the feeling it covers everything that is important and offers examples and lots of exercises. i'm not sure if itis still printed as it's quite old but it should be available in a university library.   

41

Flat Earth Debate / Re: Color Shift on stars

« on: September 22, 2009, 10:39:18 AM »

that's why you don't look at the absolute position of the lines only but also at the relative positions. i doubt you'll find two different atoms with exact the same differences in energy between the different states.

42

Technology, Science & Alt Science / Re: Mono magnetic poles

« on: September 19, 2009, 09:59:26 AM »

might fit better in the alternaive science forum.
as far as i understood these are not real monopoles. it's a dipole with both poles being separated by a relatively large distance. there's still a small flux from one pole to the second one. they only appear to be monopoles

43

Flat Earth Debate / Re: Newtonian Gravity

« on: September 18, 2009, 05:12:46 PM »

if we agree that exact mathematical representations of nature are very rare (more or less not possible) and that usefulness and quality of a theory (assuming you apply it correctly) are not necessarily dependant on overall correctness the case is settled.
(i don't want to speak for other re'ers, that's my point of view)
  

44

Flat Earth Debate / Re: Newtonian Gravity

« on: September 18, 2009, 03:36:56 AM »

when dismissing newton's law of gravity because it isn't an exact representation of reality you could as well dismiss all other physical laws as there are none that aren't aproximations to observations.

45

Flat Earth Debate / Re: Seasons - The Periodic Expander

« on: September 15, 2009, 05:53:32 PM »

in addition to 10keane's post:
london experiences summer when the sun appears small and cape town experiences summer when the sun appears large. a further distance can't explain this if earth and sun are stationary (relative positions). in the stationary case a further distance can only change the absolute value of intensity or apparent size. independant of the distance the sun will appear smallest if it is really in it's state of least expansion and vice versa.

46

Flat Earth Debate / Re: A Discussion of Bendy Light

« on: September 12, 2009, 07:18:45 AM »

just for clarification, is ea (or whatever causes bendy light) isotropic?

47

Technology, Science & Alt Science / Re: A new view of vacuum or void.

« on: September 11, 2009, 04:13:50 PM »

as far as i understood both can fall in. if the particle with positive enrgy escapes it becomes a normal particle, if the particle with negative energy escapes it becomes antimatter

48

Technology, Science & Alt Science / Re: A new view of vacuum or void.

« on: September 11, 2009, 03:34:36 PM »

yup that seems to be the point for virtual bosons

49

Technology, Science & Alt Science / Re: A new view of vacuum or void.

« on: September 11, 2009, 03:21:43 PM »

i have that book, too and had a look.
seems we are both right: virtual pairs of normal matter have positive energy. one particle is normal matter, the other antimatter (both positive energy)
virtual pairs of other matter (i guess bosons are meant but he doesn't explicitely mention them) consist of aone partner with positive and one partner with negative energy. important thing is, that they are not matter and antimatter. whenever both are separated before annihilation (eg hawking radiation) they are measured as matter or antimatter with positive energy. the transformation isn't explained (or i didn't find it) he only says that the freed partner gets scatterd in a gravitational field and is transformed into normal matter/antimatter

50

Technology, Science & Alt Science / Re: A new view of vacuum or void.

« on: September 10, 2009, 05:11:24 PM »

now to my understanding one particle has positive energy and one has negative.

nope, both have positive energy. they violate the classical conservation of energy rule but the process is covered by the uncertainty principle. (if i remember correctly you get a "-" somewhere in the equations when antiparticles are involved but that is assigned to their time propagation. so they travel backwards in time)

51

The Lounge / Re: Math Problems

« on: September 08, 2009, 05:12:29 AM »

somehow i arrived at 3pi/32 
seems i lost a factor of 2 somewhere, my solution itself seems not that bad

Winrar.  What was your method?

similar to bridget's method, i used x and the angle formed by the x-axis and AB though. that leads to

y=sin(phi)-xtan(phi)

for a given x  dy/dphi=0 leads to cos(phi)^3=x

i plugged that into the formula for y and was a bit lost cause i had no idea on how to integrate it. i showed it a mate and he somehow solved it  . seems he only wrote the remaining sine as sqrt(1-cos^2) and plugged in cos(phi)^3=x leading to bridget's integral

52

The Lounge / Re: Math Problems

« on: September 07, 2009, 05:56:16 PM »

somehow i arrived at 3pi/32 
seems i lost a factor of 2 somewhere, my solution itself seems not that bad

53

The Lounge / Re: Math Problems

« on: September 07, 2009, 05:17:24 PM »

2am over here so no guarantees: i found a solution for the upper boundary of the area, i doubt i'm able to intergrate it in finite time, a numerical solution yields an area of 0,2945.  
if that's correct i'll post the derivation of the upper boundary

54

The Lounge / Re: Math Problems

« on: September 06, 2009, 12:20:38 PM »

tbh i would have been disappointed if noone had bothered to answer.

to say somethin relevant: i thought about intergration of the area of triangles with one angle as variable but i have to find a possibility of getting the area that is counted several times in that case. i dunno if that's the way to go

55

The Lounge / Re: Math Problems

« on: September 06, 2009, 09:12:20 AM »

ah,i think i get it. one boundary is a quarter of a circle

sometimes i'm ashamed of myself  
it's clearly not a circle

edit: typo

56

The Lounge / Re: Math Problems

« on: September 05, 2009, 06:25:20 PM »

ah,i think i get it. one boundary is a quarter of a circle

57

The Lounge / Re: Math Problems

« on: September 05, 2009, 05:10:56 PM »

A line segment AB of length 1 has endpoints A, constrained to the nonnegative y axis, and B, constrained to the nonnegative x axis.  Let the region S of the xy plane be defined as follows.  A point P is in S if P lies within a right triangle formed by A, B, and the origin for some A,B satisfying the condition above.

What is the area of S?  What is the length of its boundary?  Find an equation of each smooth segment of the boundary of S in Cartesian coordinates.

i might be completely wrong but isn't that just the definition of an triangle AB0 ( A=(0,a); B=(b,0) 0=(0,0))
area is 1/2ab, lenght of boundary a+b+sqrt(a^2+b^2) , segments of the boundary are y=0 for 0<=x<=b, x=0 for 0<=y<=a and y=a-(a/b)x for 0<=x<=b

58

Technology, Science & Alt Science / Re: breaking the law

« on: August 26, 2009, 05:56:46 AM »

GR at school? 

59

The Lounge / Re: Math Problems

« on: August 23, 2009, 05:29:35 PM »

ooooold, division by 0 4th to 5th line (x-y)=0

60

Technology, Science & Alt Science / Re: Fusion

« on: August 22, 2009, 04:56:25 PM »

could you explain that second form of acceleration