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thethinkertank

How does light behave in antimatter?

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Im imagining a sort of time machine consisting of a hypothetical box made of antimatter, or coated inside in antimatter.

Now imagine passing light inside the box. Would it still obey the constant 'c'?

If not, then maybe that's the answer to creating a time machine. 

Because any particle introduced into such a box would undergo space time dilation. 

Now, CERN has plenty of that antimatter stuff, so I've heard....

 

 

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Just now, thethinkertank said:

Now imagine passing light inside the box. Would it still obey the constant 'c'?

Light speed will still be invariant; measures will be c in vacuum.

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6 minutes ago, thethinkertank said:

Now, CERN has plenty of that antimatter stuff, so I've heard....

CERN has a very minute amount at any given time. Antimatter is hard to make in quantity and hard to store.

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Just now, swansont said:

CERN has a very minute amount at any given time. Antimatter is hard to make in quantity and hard to store.

just wrap that minute amount around a hadron and watch that hadron turn into a leapin' lizard :)

Just now, Ghideon said:

Light speed will still be invariant; measures will be c in vacuum.

Are you absolutely sure of that? Antimatter cannot be controlled. Which means to some extent it exists outside the boundaries of natural forces. 

Now light, could encounter a problem with its ceaseless c'fullness so to speak, in a vaccuum coated in antimatter. 

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8 minutes ago, thethinkertank said:

Are you absolutely sure of that? Antimatter cannot be controlled. Which means to some extent it exists outside the boundaries of natural forces. 

Please learn some physics before pontificating on how nature behaves.

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Just now, swansont said:

Please learn some physics before pontificating on how nature behaves.

well, this is after all a open ended conversation. I phrased it as a question because I don't know myself. Isnt that what a scientific discussion is about? 

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4 minutes ago, thethinkertank said:

well, this is after all a open ended conversation. I phrased it as a question because I don't know myself. Isnt that what a scientific discussion is about? 

"Antimatter cannot be controlled." is not a question

"Which means to some extent it exists outside the boundaries of natural forces." is not a question.

 

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Posted (edited)
1 hour ago, thethinkertank said:

Now, CERN has plenty of that antimatter stuff, so I've heard....

The largest amount of antimatter in the Solar System is in the Sun, created and annihilated every day.. and is responsible for emission of 7.64% of the all Sun radiation..

Primary fusion reaction between two protons is creating positron and electronic neutrino. Positron is antimatter antiparticle of electron. It's annihilating with electron yielding 1.022 MeV energy (in the form of two gamma photons typically). There are two such annihilation events per single 4He created during fusion.

You can make your own antimatter (positrons) with device that cost couple hundred of dollars.

Edited by Sensei

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58 minutes ago, thethinkertank said:

just wrap that minute amount around a hadron and watch that hadron turn into a leapin' lizard :)

Are you absolutely sure of that? Antimatter cannot be controlled. Which means to some extent it exists outside the boundaries of natural forces. 

Now light, could encounter a problem with its ceaseless c'fullness so to speak, in a vaccuum coated in antimatter. 

There is nothing "uncontrollable" about antimatter.  It doesn't have any bizarre properties that you seem to imagine it has. 

We use antimatter in PET scans. Isotopes of some elements decay through the emission of positrons ( the antimatter counterpart to the electron).   These positrons then mutually annihilate with the first electron they encounter, producing a couple of gamma ray photons.    By giving a patient a small dose of a substance that contains one of these isotopes, they can use scanners to track it through the body by its positron emissions. 

What is difficult to do with antimatter is store it on Earth in any great quantities.  When antimatter comes in contact with "normal" matter, they mutually annihilate each other.  Since any antimatter we make is surrounded by regular matter, the trick is to keep the two apart.   This is done by using "magnetic bottles" which hold the antimatter in a vacuum and use electric and magnetic fields to keep it from touching the material walls ( this in itself shows that antimatter is controllable with natural forces.   Even then, we can't store it for too long.  We can't produce a perfect vacuum, which means the antimatter is still going to encounter stray atoms over time and slowly be "eroded" away. 

The log term storage of antimatter is a technological issue and not one due to some "uncontrollable" nature of antimatter.

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1 hour ago, thethinkertank said:

Are you absolutely sure of that?

Yes.

 

Which of course means I will change my opinion as soon as a new model where c is not invariant is presented, supported by credible experimental results and generally accepted in mainstream science. I'm also sure this forum will note be the first location where such ground breaking results will be found.

 

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3 hours ago, thethinkertank said:

Now imagine passing light inside the box. Would it still obey the constant 'c'?

Yes.

3 hours ago, thethinkertank said:

If not, then maybe that's the answer to creating a time machine. 

No.

2 hours ago, thethinkertank said:

Are you absolutely sure of that? Antimatter cannot be controlled. Which means to some extent it exists outside the boundaries of natural forces. 

The reason that CERN are able to produce anti-matter and measure its properties is because it can be controlled.

And the properties they measure show it to behave exactly like ordinary matter (not "outside the boundaries of natural forces").

2 hours ago, thethinkertank said:

well, this is after all a open ended conversation. I phrased it as a question because I don't know myself. Isnt that what a scientific discussion is about? 

You didn't phrase it as a question: you made two confident (and incorrect) assertions. Maybe you should stick to asking questions for a while.

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Posted (edited)
13 minutes ago, Strange said:

And the properties they measure show it to behave exactly like ordinary matter (not "outside the boundaries of natural forces"). 

That depends on what property of matter and antimatter you're examining. If in applied external electric field and/or magnetic field electron flies to the left, or circle left, positron is doing exactly mirror-like action and flies, or making circles, to the right. That's what is used to distinguish electron from positron. Mirror-like behavior in the same experiment. Due to opposite quantum number for e.g. charge q.

Edited by Sensei

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9 minutes ago, Sensei said:

That depends on what property of matter and antimatter you're examining. If in applied external electric field and/or magnetic field electron flies to the left, or circle left, positron is doing exactly mirror-like action and flies, or making circles, to the right. That's what is used to distinguish electron from positron.

Clearly, a particle with opposite charge moves in the opposite direction. That is true whether it is an antimatter particle, or a particle with the opposite charge. 

So the behaviour of antimatter is described by exactly the same equations as matter. (Apart from the very small violations of CP symmetry.)

2 hours ago, thethinkertank said:

just wrap that minute amount around a hadron and watch that hadron turn into a leapin' lizard

How are you going to do that if "antimatter cannot be controlled"? (Apart from the fact that "wrapping it around a hadron" is a completely meaningless phrase.)

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Just now, Janus said:

There is nothing "uncontrollable" about antimatter.  It doesn't have any bizarre properties that you seem to imagine it has. 

We use antimatter in PET scans. Isotopes of some elements decay through the emission of positrons ( the antimatter counterpart to the electron).   These positrons then mutually annihilate with the first electron they encounter, producing a couple of gamma ray photons.    By giving a patient a small dose of a substance that contains one of these isotopes, they can use scanners to track it through the body by its positron emissions. 

What is difficult to do with antimatter is store it on Earth in any great quantities.  When antimatter comes in contact with "normal" matter, they mutually annihilate each other.  Since any antimatter we make is surrounded by regular matter, the trick is to keep the two apart.   This is done by using "magnetic bottles" which hold the antimatter in a vacuum and use electric and magnetic fields to keep it from touching the material walls ( this in itself shows that antimatter is controllable with natural forces.   Even then, we can't store it for too long.  We can't produce a perfect vacuum, which means the antimatter is still going to encounter stray atoms over time and slowly be "eroded" away. 

The log term storage of antimatter is a technological issue and not one due to some "uncontrollable" nature of antimatter.

quite a lucid explanation. 

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17 hours ago, thethinkertank said:

quite a lucid explanation. 

The best thing you can do at this point instead of posting more threads and more posts of your own for the the next week or so, is read through Janus’s posts on this forum in various threads. Do yourself a favor and do as I suggest.

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2 minutes ago, koti said:

The best thing you can do at this point instead of posting more threads and more posts of your own for the the next week or so, is read through Janus’s posts on this forum in various threads. Do yourself a favor and do as I suggest.

Oh, aye. The very best thing.

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On 6/17/2019 at 10:36 AM, Sensei said:

The largest amount of antimatter in the Solar System is in the Sun, created and annihilated every day.. and is responsible for emission of 7.64% of the all Sun radiation..

Primary fusion reaction between two protons is creating positron and electronic neutrino. Positron is antimatter antiparticle of electron. It's annihilating with electron yielding 1.022 MeV energy (in the form of two gamma photons typically). There are two such annihilation events per single 4He created during fusion.

You can make your own antimatter (positrons) with device that cost couple hundred of dollars.

Just a related tidbit. I recall reading that a typical banana releases 1 positron about every hour. Evidentally it is from the decay of potassium-40. Unfortunate that we are not able to harvest each and every one of those positrons...it could add up over time to something substantial in my view:(

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15 hours ago, The Shadow said:

Just a related tidbit. I recall reading that a typical banana releases 1 positron about every hour. Evidentally it is from the decay of potassium-40. Unfortunate that we are not able to harvest each and every one of those positrons...it could add up over time to something substantial in my view:(

Since the Potassium in a banana isn't going to have any higher a ratio of K-40 than any other natural source of Potassium, if you are thinking in terms of health issues, you have nothing to be concerned about.  A person would have to ingest 1000 bananas in one sitting to get enough radiation to increase your risk of death by 1 part in a million.

There are no "accumulative" effects either. Potassium is one of those elements that the body carefully regulates.  Ingest potassium rich foods, and the body just takes what it needs to maintain levels and the rest is expelled as waste.   So you can't get a "build up" of K-40 in your body, and any K-40 in your body is going to be due to the potassium your body needs to function properly.  So the only way you could avoid K-40 in your body is to avoid eating all naturally occurring Potassium sources (which encompasses quite a lot of food), and get your potassium via supplements, which have had the K-40 removed. Likely a very involved and expensive process, and unlikely worth it considering the low level risk natural K-40 levels in you body represent.  If you are going to fret over that, you'd go absolutely ballistic over the carbon-14 in your body)

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4 hours ago, Janus said:

Since the Potassium in a banana isn't going to have any higher a ratio of K-40 than any other natural source of Potassium, if you are thinking in terms of health issues, you have nothing to be concerned about.  A person would have to ingest 1000 bananas in one sitting to get enough radiation to increase your risk of death by 1 part in a million.

There are no "accumulative" effects either. Potassium is one of those elements that the body carefully regulates.  Ingest potassium rich foods, and the body just takes what it needs to maintain levels and the rest is expelled as waste.   So you can't get a "build up" of K-40 in your body, and any K-40 in your body is going to be due to the potassium your body needs to function properly.  So the only way you could avoid K-40 in your body is to avoid eating all naturally occurring Potassium sources (which encompasses quite a lot of food), and get your potassium via supplements, which have had the K-40 removed. Likely a very involved and expensive process, and unlikely worth it considering the low level risk natural K-40 levels in you body represent.  If you are going to fret over that, you'd go absolutely ballistic over the carbon-14 in your body)

Since ~11% of the K-40 decays gives off 1.46 MeV gammas (from electron capture; the positron branch is very small), which means it easily escapes the banana or potato (or other food it's in), I'd avoid the produce section of the grocery store if one thinks this exposure is a problem.

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On 8/26/2019 at 1:06 PM, Janus said:

Since the Potassium in a banana isn't going to have any higher a ratio of K-40 than any other natural source of Potassium, if you are thinking in terms of health issues, you have nothing to be concerned about.  A person would have to ingest 1000 bananas in one sitting to get enough radiation to increase your risk of death by 1 part in a million.

There are no "accumulative" effects either. Potassium is one of those elements that the body carefully regulates.  Ingest potassium rich foods, and the body just takes what it needs to maintain levels and the rest is expelled as waste.   So you can't get a "build up" of K-40 in your body, and any K-40 in your body is going to be due to the potassium your body needs to function properly.  So the only way you could avoid K-40 in your body is to avoid eating all naturally occurring Potassium sources (which encompasses quite a lot of food), and get your potassium via supplements, which have had the K-40 removed. Likely a very involved and expensive process, and unlikely worth it considering the low level risk natural K-40 levels in you body represent.  If you are going to fret over that, you'd go absolutely ballistic over the carbon-14 in your body)

I am not sure why you quoted and replied to me with heath concern discussion. I never mentioned anything of the sort in my message. My comment was referencing the harvesting...along with the unfortunate ability to do it from bananas.

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