Laymans question about observational effect

[GUS]

Could someone please explain in laymans terms if possible how the process of effecting things by observing them actually works.
Perhaps rather pretentiously me and a friend are having a dispute. He is saying its simply a matter of the measuring device bouncing photons or whatever off whatever you are trying to measure (or observe).
However I have rather ambitiously considering how ill informed I am , said that this is not the case but the actual act of observation seems to effect the observed without there necessarily being any physical copntact - until you observe it it actually exists in more than one state.
So how do you observe these tiny things exactly ?

 

[LostConjugate]

You must absorb some energy in order to measures anything. So by measuring you always interfere with the particle. Absorbing a photon is tricky as you need to absorb enough energy to make a measurement and you would likely have no photon left. It might be possible to have a high energy photon and take a bit of it's kinetic energy away, however in order for a photon to give up any kinetic energy it must be localized at that moment which would collapse the wave function.

This act of a wave localizing to a particle when measured is in large what QM is all about. Every time we measure a particle it is only ever in one location, though QM proposes that before we measures it, it is a wave covering all space. And only with this explanation do our calculations meet experimental results because all particles have wave like properties in many experiments (double slit, Q tunneling, etc)

 

[Matterwave]

Theoretically speaking, you are correct. The act of "observing" (whatever that means in this case) will collapse the wavefunction from a mixture of eigenstates of the observable into one eigenstate of that observable. This is a fundamental postulate of standard QM, and requires no interpretation into the method of observing. Whatever can theoretically constitute an observation, can collapse the wave-function.

However, physically speaking, you MUST interact with the particle in some way in order to observe it. So, the physical mechanism that will make the collapse occur is interaction.

 

[GUS]

I think my friend thinks observing the particle is a bit like trying to assess the position of a snooker ball on a snooker table by bouncing another snooker ball off it.
However in the case of Schrodingers cat the observation is merely observing which of two holes the particle has passed through - no interatcion is actuially postulated other than observing which route the particle took in the past.
Is my friend correct with his snooker ball analogy - is that the real reason that w effect the result by observing it - a simple matter of causality - or is it more complex ?
To really understand quantum physics properly what areas of mathematics and physics would I need to study (I don't have the opportunity to study a whole physics degree at the moment - I was wonderin if I could just read the relevant parts) ? The last thing i remember are quadratic equations - however I am prepared to learn the maths and physics necessary to gain a better understanding of the theory - I find it intriguing.

 

[LostConjugate]

http://ocw.mit.edu/OcwWeb/Physics/8-03Fall-2004/CourseHome/index.htm
For a solid foundation of wave mechanics

Then...

http://www.youtube.com/view_play_list?p=0F530F3BAF8C6FCC
For an introduction to LVS and QM Core, less mathematical

Then..

http://physicsstream.ucsd.edu/courses/spring2003/physics130a/
For in-depth mathematical QM CoreMATH
If you have not taken Calc, you will need:
http://tutorial.math.lamar.edu/Classes/CalcI/CalcI.aspx
You need to know LA
http://tutorial.math.lamar.edu/Classes/LinAlg/LinAlg.aspx
You need to understand DEs
http://tutorial.math.lamar.edu/Classes/DE/DE.aspxIf that is just too much, then check out this non-mathematical book which goes in-depth on the double slit experiments and others:

https://www.amazon.com/dp/0375708111/?tag=pfamazon01-20

 

[GUS]

http://ocw.mit.edu/OcwWeb/Physics/8-03Fall-2004/CourseHome/index.htm
For a solid foundation of wave mechanics

Then...

http://www.youtube.com/view_play_list?p=0F530F3BAF8C6FCC
For an introduction to LVS and QM Core, less mathematical

Then..

http://physicsstream.ucsd.edu/courses/spring2003/physics130a/
For in-depth mathematical QM CoreMATH
If you have not taken Calc, you will need:
http://tutorial.math.lamar.edu/Classes/CalcI/CalcI.aspx
You need to know LA
http://tutorial.math.lamar.edu/Classes/LinAlg/LinAlg.aspx
You need to understand DEs
http://tutorial.math.lamar.edu/Classes/DE/DE.aspxIf that is just too much, then check out this non-mathematical book which goes in-depth on the double slit experiments and others:

https://www.amazon.com/dp/0375708111/?tag=pfamazon01-20

No that's not too much at all, I realize this willl take time but I am determined -so I will start with calculus - you could never get me to do this at school and now look - volunteering ! - thankyou very much for your help !