[mattmckee (OP)]

How exact does the energy of a photon have to be to excite an electron to the next energy level?  (not ionisation as thats just a minimum energy).

Thanks
Matt

[Bored chemist]

The annoying answer is "it depends"

https://en.wikipedia.org/wiki/Spectral_line#Line_broadening_and_shift

[Hayseed]

It's not the amount of energy, it's the rate.  Trying to understand our physical reality thru the study of mass and energy will always lead you down a false path.

The reason that all physical dynamics are the same thru-out the cosmos.......is NOT because of energy and mass.

What unifies all............is structure.  ONE STRUCTURE.  That structure is what causes the discreet property of energy.  The structure manufactures and orientates all of the physical properties.

Talking or premising structure on the sub atomic level is forbidden in our modern science.

This is why they can not relate EM to gravity.  This structure ties everything together with common mechanics.

But modern science preaches that reality can not be understood in a physical manner.

It has to have magic.

If you take a proton, reverse it's time line, accelerate it, it will become a positron.  That positron will have the exact same energy levels as an electron.  If you take an electron, reverse it's time line. accelerate it, it will become an anti-proton.........AND it will have the exact same energy levels as a proton.

WHY?   

structure.  They have the same structure.

[alancalverd]

Hayseed indeed. An argument straight from the floor of the bull's pen.

[evan_au]

If you take an electron, reverse it's time line. accelerate it, it will become an anti-proton...

Protons & antiprotons are made of quarks. Electrons and positrons aren't made of quarks.
Accelerating an electron won't make it have quarks.

Protons & antiprotons are baryons, with integer spin. Electrons and positrons are Fermions with half-integer spins.
Accelerating an electron won't make it have integer spin.

[Bored chemist]

It's not the amount of energy, it's the rate.  Trying to understand our physical reality thru the study of mass and energy will always lead you down a false path.

The advantage to using mass and  energy is that they are (collectively)  conserved.
But the rate of energy transfer, i.e. power, is not conserved.
So it's only generally possible to do calculations on energy and mass (and momentum) but not power (or rate).

So the assertion is fundamentally wrong.
It's not just a matter of "well that's what conventional physics thinks but I know better".
It's wrong.

[Bored chemist]

It's not the amount of energy, it's the rate.  Trying to understand our physical reality thru the study of mass and energy will always lead you down a false path.

The advantage to using mass and  energy is that they are (collectively)  conserved.
But the rate of energy transfer, i.e. power, is not conserved.
So it's only generally possible to do calculations on energy and mass (and momentum) but not power (or rate).

So the assertion is fundamentally wrong.
It's not just a matter of "well that's what conventional physics thinks but I know better".
It's wrong.

It has to have magic.

If you take a proton, reverse it's time line, accelerate it, it will become a positron. 

Reversing time is magic.
On the other hand, science doesn't do magic.
What point did you think you were making?

[KarmenX]

No spam please, we're British.

[jeffreyH]

Go to a supermarket. You are the weakest link. GOODBYE!