Question

Example of any 2 particles which do not exert Gravitational force on each other?

Answer 1

@experimentX @Mashy

Answer 2

photons? :P

Answer 3

I thought of photon but its not exactly massless..it has SOME mass so negligible..but no 0

Answer 4

timing:D

Answer 5

ermm.. is it?.. i thought it had no mass :D

Answer 6

\[\LARGE M_{p}=1.8 \times 10^{-42}g\]

Answer 7

omg.. :O.. where did you get that from? :O..
anwyays.. there are no particles then without gravity as far as i know :O

Answer 8

if photons dont have mass how do they have momentum?

Answer 9

that is really more subtle than you think..
when light can act like both particle and wave... which itself is mind boggling.. you think it not having mass but having momentum is a big deal? :P

Answer 10

lol

Answer 11

You measure gravitational force on particles that's at a quantum level, which involves photons. In QM photons are considered to have a rest mass of 0, so I guess the only answer is photon. Higgs to come?

Answer 12

Higgs is massless?

Answer 13

DLS look into photoelectric effect derivation and compton scattering

Answer 14

but you know what??

think of this .. if two photons of light are moving parallel to each other(in vacuum)... if they put force of gravity on each other, then their velocities WOULD CHANGE right.. i don't care how small that change is.. but it would change.. ?? but remember relativity?? light cannot have ANY OTHER speed than C.. in vacuum.. regardless of what crap you do!!..
so they cannot put gravitational force on each other :O

hmm.. how is that argument? :O

Answer 15

for why it has momentum, no higgs would give more knowledge, it gives mass.

Answer 16

i know photoelectric effect

Answer 17

or maybe not.. you can use general relativity to explain that.. so never mind :D

Answer 18

The Standard Model's explanation of why some fundamental particles have mass when 'naive' theory says Higgs boson should be massless

Answer 19

so can we say photon photon and boson boson :O

Answer 20

@Mashy dude stop showing off relativity in every question of mine when u know i dont understand it :P

Answer 21

Photoelectric determines relationship between energy and frequency ... E proportional to (a + bw) where w = angular omentum

so E = Hbar(w-w_a) = h(v - v_a)

photon rest mass is zero for general relation of energy, so it can be written as

E^2 = (m_0*c^2)^2 + p^2c^2 = Hbar^2w^2

and can cancel to momentum p = Hbar * k, where k = w/c (wave number)

therefore the momentum of a photo can be given as p = Hbar * k

bear in mind wave particle duality, how a wave can have momentum is a toughy, yet quite beautiful

Answer 22

wait for @Iamgmg90

something bombastic is on its way.. either that

or his computer is stuck :D

Answer 23

ok sorry DLS :P.. didn't mean to!

Answer 24

Bombastic haha, its just my understanding I hope it shed light on the matter, excuse the pun :P

Answer 25

guys im a sweet little cute innocent student :3

Answer 26

simple answers should be awesome :P

Answer 27

Trying to word equations in english and failing, I don't think quantum mechanics could be simple hehe, are you a student of physics?

Answer 28

yes..XIth grade

Answer 29

11th grade? I have no idea what that is, I'm English

Answer 30

is that high school?

Answer 31

kinda

Answer 32

I think the main part of understand that is knowing planck's constant well

Answer 33

& the difference between h and hbar

Answer 34

yes,ive read about atomic struc

Answer 35

not hbar

Answer 36

its just h / 2pi

Answer 37

but not just, very important for its relationship with angular frequency

Answer 38

omg sorry in those equations w = angular frequency, not momentum

Answer 39

\[mvr=\frac{nh}{2\pi}\]

Answer 40

:o

Answer 41

Bohr is far from QM, but orbital win

Answer 42

anyway,thanks guys! ill go with photon for meanwhile :P and/or bosson

Answer 43

from where Bosson came?? bossons have mass :O !!!

Answer 44

http://prntscr.com/tqp5w

Answer 45

naive theory \m/

Answer 46

so? it still says higg's particle gives mass!

Answer 47

okay photon :P

Answer 48

higg's particle has been discovered hello!??

Answer 49

oops I cant give medal to myself D:

Answer 50

super large hardron collider??

Answer 51

oout off my syllabus :P

Answer 52

geneva switzerland?? .. 7.7TEV??? hello?!?!

Answer 53

:| thanks everyone