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Specialty Chemistry Forums => Nuclear Chemistry and Radiochemistry Forum => Topic started by: Ashutosh on March 20, 2005, 11:25:53 AM

Title: positron
Post by: Ashutosh on March 20, 2005, 11:25:53 AM
I have read the following in the newspaper about positron.
 Paul Derac established the concept of positron.He stated that positron has no mass but has possitive charge.This means,positron is non-existant(as it is massless)How any massless thing can have charge ???
 It is also stated that positron can go in the direction opposite to that
of time ( the past-tence).How is it possible ???
  if this is possible,then will it help to go into the past :excl:
 thank you
Title: Re:positron
Post by: Mitch on March 20, 2005, 11:31:56 AM
It is just the antiparticle of the electron. It does have a mass its 0.511 MeV.

It doesn't travel backwards in time the way you are thinking, it would be to difficult to explain though.
Title: Re:positron
Post by: Ashutosh on March 20, 2005, 11:59:38 AM
thanks for explanation mitch
  i dont get the idea yet.The thinking,positron can go in past ,is not mine.Paul Derac had stated this..He got nobel prize.I may be wrong in translating
    please explain it to me again.
 thank you.
Title: Re:positron
Post by: Mitch on March 20, 2005, 06:28:42 PM
It won't make sense, I don't want to waste time explaining the finer points of quantum electro dynamics if you don't know the basics. Buy a particle physics book and it'll all be in there.

He got the nobel prize because he made a theory that could predict and explain the date he observed. In it, positrons have to travel backwards in time. But, don't get confused, I make positrons all the time in lab and they behave physically just as an electron does except they have a positive charge.
Title: Re:positron
Post by: minibee041 on June 10, 2005, 07:03:08 AM
Hi Mitch just registered as i have been redirected a few imes to sites like this for various questions.  I'm a fireman by day but enjoy learning and due to my inquisitive personality fallen lately into QED largely due toa documentry on one Mr R.P. Feynman.  He was intoxicating and i hd to find out more.  I have read and am currently rereading QED - Strange theory of light and matter to further my understanding.  However i am still puzzled by the apparent 'time-travelling' capabilities of positrons.  I have some understanding and i know i am only scratching the surface but please can you help.  I hope you give me more patience and time than you did Ashutosh.  My question's are;  In what capacity do postrons 'time travel'?. What influences the decision to go forwards or backwards and when they were first formed shortly after the big bang what happened if they preceded the time before they were in existence? As it is hard to answer in few words these questions it is also difficult to word questions correctly with small amopunts of knowledge.  Thank you for your time
Title: Re:positron
Post by: Mitch on June 10, 2005, 12:36:13 PM
Okay, your going to make me dust off the old particle physics book; I'll get a better answer for you before the end of the day. But, for all practical purposes a positron is just and electron with a positive charge. You can make them in a laboratory and you can control them just as you would control an electron, its not  something strange to deal with. The theory that governs their behavior says they travel backwards in time, but if the theory didn't say it did, you could never tell they did in a laboratory, since they behave exactly like electrons except positively charge.
Title: Re:positron
Post by: minibee041 on June 10, 2005, 04:54:11 PM
Awesome, my missus has told me i was harsh in one of my comments to you earlier and having read it again i was....sorry.  Well, another question answered i will look more into this.  Theoretical and Quantum Physics has reawakened my desire to learn and this message board is a great way of gleening information!! Thank you again.  "What one fool can do, another can" as Feynman put it! It just takes this fool a bit longer! :P
Title: Re:positron
Post by: constant thinker on June 10, 2005, 10:49:42 PM
Ok I'm wondering about this one here. What has to happen, generally speaking, for a positron to form. I know that anti-matter is released in particle colliders.