UFO's

[Xaccers]

Originally Posted by towny

Newton came up with Newtonian physics (so it's a good job he wasn't called smith!)
F=MA

That works with most things (hence why GCSE physics teaches it) but it's not perfect.
Newton knew this but didn't know the mathematics to fix the problem, like with Mercury's orbit.

Originally Posted by trebor

who decided what the speed of light was, what if it was measured wrong, what if it's not as fast as you all think
how many laws of physics have already been adjusted to fit in with modern thinking ?

they said we could not travel faster than 30mph, they said we could not fly
the list goes on, but they were wrong

But the point is that this is *science*.

If someone claims that "we cannot fly" or "we'll die if we travel over 100 mph" someone else can go out and do an experiment and either prove them right or wrong.

Then yet another person will go over the second person's results and check to see they didn't make any mistakes.

It was originally thought that the speed of light was inifinite, simply because those thinkers didn't have the ability to measure it. Then it was measured, corrected, measured again and it was stated that the speed of light was constant. Then someone else looked at the details and said "hang on, no, it's not constant, it can change in certain circumstances..."

Science constantly evolves and changes as we learn more, so, to quote Arthur C Clarke's personal "three laws:

1) "When a distinguished but elderly scientist states that something is possible he is almost certainly right. When he states that something is impossible, he is very probably wrong."

2) "The only way of discovering the limits of the possible is to venture a little way past them into the impossible."

3) "Any sufficiently advanced technology is indistinguishable from magic."

http://www.lsi.usp.br/~rbianchi/clarke/ACC.Laws.html

(Gregory Benford came up with a corollory to Clarke's third law: Any technology that is distinguishable from magic is insufficiently advanced!)

Originally Posted by Graham

But the point is that this is *science*.

If someone claims that "we cannot fly" or "we'll die if we travel over 100 mph" someone else can go out and do an experiment and either prove them right or wrong.

Then yet another person will go over the second person's results and check to see they didn't make any mistakes.

It was originally thought that the speed of light was inifinite, simply because those thinkers didn't have the ability to measure it. Then it was measured, corrected, measured again and it was stated that the speed of light was constant. Then someone else looked at the details and said "hang on, no, it's not constant, it can change in certain circumstances..."

Science constantly evolves and changes as we learn more, so, to quote Arthur C Clarke's personal "three laws:

1) "When a distinguished but elderly scientist states that something is possible he is almost certainly right. When he states that something is impossible, he is very probably wrong."

2) "The only way of discovering the limits of the possible is to venture a little way past them into the impossible."

3) "Any sufficiently advanced technology is indistinguishable from magic."

http://www.lsi.usp.br/~rbianchi/clarke/ACC.Laws.html

(Gregory Benford came up with a corollory to Clarke's third law: Any technology that is distinguishable from magic is insufficiently advanced!)

very true, I think one of the 'problems' we have with physics, especially, is that a lot of the theory is just that. Einsteins work was initially based solely on mathematics, rather than experiment. When we were able to try to verify the theory, a lot of his conclusions turned out to be very close to the observations, but there were enough anomalies to beg further questions. This is currently being theorised in the various incarnations of string theory & supersymmetry, but again this remains, for now, a purely mathematical exercise. The scientists hope that the new particle accelerators due to come on-line soon e.g the one at CERN, will shed fresh light on the quest for 'the theory of everything'.

If some of this work bears fruit we may be looking at understanding antigravity & who knows what else - something to show the 'little green men', when they arrive.

[Xaccers]

Problem is poor reporting by the media, a scientist publishes a theory, the newspapers get hold of it, mis-report and the public, not knowing how science as an institute really works, believes that the scientists are proclaming it as a definite rather than a theory

[trebor]

Originally Posted by Xaccers

E=MC^2
We all know it, but do you know what the letters stand for?

E is energy
M is mass
C is the speed of light

therefore using a bit of arabic we get

C=square root (E/M)

So as speed increases, Energy and mass increases.
Something like that anyway.

Now, faster than light travel is theologically possible, although what you really do is take a short cut bye folding or warping spacetime

so what about the faster than light negative mass tachyons? where do they fit in

[dilli-theclaw]

Originally Posted by trebor

so what about the faster than light negative mass tachyons? where do they fit in

Surely if they are travelling faster than light then they don't fit in NOW but at some point in the past

[trebor]

Leptons, Quarks, and Black Holes

my head hurts now, but one more for you clever folks, if mass increases with speed, how heavy is light? no pun intended.

Originally Posted by trebor

so what about the faster than light negative mass tachyons? where do they fit in

ooh this will get me googling, but afaik the 'latest' versions of supersymmetry theory don't include tachyons - & wasn't the mass 'imaginary' rather than negative?

Originally Posted by trebor

Leptons, Quarks, and Black Holes

my head hurts now, but one more for you clever folks, if mass increases with speed, how heavy is light? no pun intended.

That's what I was wondering. I remember reading somewhere that scientists can't agree whether light is a wave or a particle, as it has characteristics of both. If it is some kind of wave, then presumably weight is irrelevant?

/head throbs

[trebor]

Originally Posted by homealone

ooh this will get me googling, but afaik the 'latest' versions of supersymmetry theory don't include tachyons - & wasn't the mass 'imaginary' rather than negative?

I suppose you are right, tachyons are still a theory unless something has changed recently, but theory or not the maths looks good for there existence.

Originally Posted by trebor

I suppose you are right, tachyons are still a theory unless something has changed recently, but theory or not the maths looks good for there existence.

A theory? Well I hope for Star Trek's sake it's eventually proven. Otherwise about 75% of Voyager episodes will look even more stupid ...

Originally Posted by towny

That's what I was wondering. I remember reading somewhere that scientists can't agree whether light is a wave or a particle, as it has characteristics of both. If it is some kind of wave, then presumably weight is irrelevant?

/head throbs

they have the same 'problem' with electrons, interestingly electrons do have mass, wheras photons are considered massless - but apparently have momentum????

Originally Posted by trebor

my head hurts now, but one more for you clever folks, if mass increases with speed, how heavy is light? no pun intended.

Current theory (AIUI) is that photons have no mass so they're not affected.