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Wow this is the first time I heard about unstable vacuum and that > the universe could in theory spontaneously explode at some point releasing huge amounts of

by yread 15y ago

Wow this is the first time I heard about unstable vacuum and that > the universe could in theory spontaneously explode at some point releasing huge amounts of energy as it fell into a more stable lower energy vacuum state. This catastrophe would spread across the universe at the speed of light in an unstoppable wave of heat that would destroy everything in its path. Also >instability could also set in at energies around a million TeV .. so if LHC was million times more powerful it could explore such instabilities i.e push the vacuum out of the metastable state and trigger the scenario above!? It seems I wasn't giving enough credit to the religious nuts saying that LHC will destroy the world

Sharlin 15y ago
Yes; triggering a vacuum collapse is one of the three (EXTREMELY hypothetical) doomsday scenarios associated with high-energy particle accelerators: * Triggering the collapse of the vacuum to a more stable state * Production of strangelet particles that convert everything to more strangelets * Production of microscopic black holes that eventually swallow the Earth First of all, all three require hypothetical extensions to currently accepted physics, but the most compelling argument against these being possible is the fact that thousands and millions of times more energetic events than what LHC is capable of occur all around the Universe all the time, including in Earth's upper atmosphere, and we're still here. See http://user.web.cern.ch/public/en/LHC/Safety-en.html http://user.web.cern.ch/public/en/LHC/Safety-en.html
- maeon3 15y ago
  Also, assuming there are advanced civilizations in our visible universe, none of them have produced a universe destroying event... At least not for the last 14 billion years. We are safe. everything going on at the lhc has already happened Near the earth. On the plus side, if something does go wrong, you wont get a chance to worry about it.
  - jordanb 15y ago
    I don't think we have to go that far. These particles exist in nature, but not conveniently here on earth in the vicinity of test equipment. The Universe produces very high energy events all the time -- supernova among others -- and many of these have happened within our light cone, yet have not thrown a wave of new vacuum at us.
    - sp332 15y ago
      Since the expansion happens at the speed of light, we would have no advance warning. We couldn't "see" the event approaching us, since the event would arrive at the same time as the light from it.
      - JanezStupar 15y ago
        That is if the event would have been instantaneous. Otherwise it would probably be the most beautiful phenomena possible. Also this event might have happened somewhere in the universe and never reach us. Right?
        sp332 15y ago
        Let's say the event happens 4 light-years away from us. It's not traveling instantaneously, it's only traveling at the speed of light. So it will take 4 years to get here. But we will never see it, because the light from the event will also take 4 years to get here, so we will be destroyed at the same time that the light from the event arrives.
        JanezStupar 15y ago
        Well if the phenomena was not instantaneous and would have some sort of "flash" preceding the shock wave, for a couple of minutes. It could be visible. And anything on that scale would be extremely bright and beautiful. Its just an alternative to black wall you will never see or feel. But honestly I have no idea which one is more likely.
  - finnw 15y ago
    Or maybe they have, and it has yet to reach us.
    - stouset 15y ago
      Then we'd better strike first.
  - deleted 15y ago
    [deleted]
  - civilian 15y ago
    The earliest that sentient life could develop is probably ~5 billion years after the big bang. So you should only count the last 9 billion years. :D (I'm basing it off of: 1 billion years for a star to form & explode to provide the heavier elements needed for a rocky planet. Another 1 billion years for a new solar system to form, another billion years for the rocky inner planet to cool off, another 1 billion for simple life to develop, and then another billion for intelligent life to develop.)
Tuna-Fish 15y ago
> .. so if LHC was million times more powerful it could explore such instabilities i.e push the vacuum out of the metastable state and trigger the scenario above!? It seems I wasn't giving enough credit to the religious nuts saying that LHC will destroy the world Note that if LHC was capable of this, it would have already happened. Ultra-high-energy cosmic rays are detected occasionally, and statistically, they hit Earth more than once per day. The highest energy ever detected was a particle with 3*10^20 eV, or 300,000,000 TeV, or roughly as much kinetic energy that a baseball has at 60mph, in what was likely a single proton. It was aptly named the "Oh-My-God particle".
andrewcooke 15y ago
it wasn't just religious nuts - i was worried myself (i may be a nut, but i am certainly not religious!) - and most people dismissing the worries on the internet were "science groupies" without a detailed understanding of the issues (in my experience, at the time, as far as i recall, etc). thankfully, there was a good report written that addressed the concerns in substantial detail. if you haven't read it, it's very interesting (and moderately reassuring) - http://cdsweb.cern.ch/record/613175/files/CERN-2003-001.pdf?version=1 http://cdsweb.cern.ch/record/613175/files/CERN-2003-001.pdf?... [ps an example of how simple arguments are not necessarily right is that any black hole created by the lhc would be almost at rest in the frame of the collider, unlike expected products from astronomical processes; that means that it would be gravitationally bound, allowing the effects of a small cross-section to accumulate over time. this isn't advanced physics, by any stretch of the imagination, yet people never seem to address it. another issue is that planets may indeed be destroyed by cosmic processes - at the time the lhc was being designed we had very little in the way of statistics on the number of planets or their lifetimes, outside of our own solar system.]
- philipn 15y ago
  Did you find an exploration of the gravitationally-bound black hole idea? I've been wondering the same thing since reading about this a few years ago.
Florin_Andrei 15y ago
No reason to worry as long as we're not matching Mother Nature yet in terms of energy. We're not even close. She's doing a lot more nasty things, even here on Earth, on a daily basis. Nothing's happened as a result. So we'll be fine.

by yread 15y ago

Sharlin 15y ago

Yes; triggering a vacuum collapse is one of the three (EXTREMELY hypothetical) doomsday scenarios associated with high-energy particle accelerators: * Triggering the collapse of the vacuum to a more stable state * Production of strangelet particles that convert everything to more strangelets * Production of microscopic black holes that eventually swallow the Earth First of all, all three require hypothetical extensions to currently accepted physics, but the most compelling argument against these being possible is the fact that thousands and millions of times more energetic events than what LHC is capable of occur all around the Universe all the time, including in Earth's upper atmosphere, and we're still here. See http://user.web.cern.ch/public/en/LHC/Safety-en.html http://user.web.cern.ch/public/en/LHC/Safety-en.html

maeon3 15y ago
Also, assuming there are advanced civilizations in our visible universe, none of them have produced a universe destroying event... At least not for the last 14 billion years. We are safe. everything going on at the lhc has already happened Near the earth. On the plus side, if something does go wrong, you wont get a chance to worry about it.
- jordanb 15y ago
  I don't think we have to go that far. These particles exist in nature, but not conveniently here on earth in the vicinity of test equipment. The Universe produces very high energy events all the time -- supernova among others -- and many of these have happened within our light cone, yet have not thrown a wave of new vacuum at us.
  - sp332 15y ago
    Since the expansion happens at the speed of light, we would have no advance warning. We couldn't "see" the event approaching us, since the event would arrive at the same time as the light from it.
    - JanezStupar 15y ago
      That is if the event would have been instantaneous. Otherwise it would probably be the most beautiful phenomena possible. Also this event might have happened somewhere in the universe and never reach us. Right?
      - sp332 15y ago
        Let's say the event happens 4 light-years away from us. It's not traveling instantaneously, it's only traveling at the speed of light. So it will take 4 years to get here. But we will never see it, because the light from the event will also take 4 years to get here, so we will be destroyed at the same time that the light from the event arrives.
        JanezStupar 15y ago
        Well if the phenomena was not instantaneous and would have some sort of "flash" preceding the shock wave, for a couple of minutes. It could be visible. And anything on that scale would be extremely bright and beautiful. Its just an alternative to black wall you will never see or feel. But honestly I have no idea which one is more likely.
- finnw 15y ago
  Or maybe they have, and it has yet to reach us.
  - stouset 15y ago
    Then we'd better strike first.
- deleted 15y ago
  [deleted]
- civilian 15y ago
  The earliest that sentient life could develop is probably ~5 billion years after the big bang. So you should only count the last 9 billion years. :D (I'm basing it off of: 1 billion years for a star to form & explode to provide the heavier elements needed for a rocky planet. Another 1 billion years for a new solar system to form, another billion years for the rocky inner planet to cool off, another 1 billion for simple life to develop, and then another billion for intelligent life to develop.)

Tuna-Fish 15y ago

> .. so if LHC was million times more powerful it could explore such instabilities i.e push the vacuum out of the metastable state and trigger the scenario above!? It seems I wasn't giving enough credit to the religious nuts saying that LHC will destroy the world Note that if LHC was capable of this, it would have already happened. Ultra-high-energy cosmic rays are detected occasionally, and statistically, they hit Earth more than once per day. The highest energy ever detected was a particle with 3*10^20 eV, or 300,000,000 TeV, or roughly as much kinetic energy that a baseball has at 60mph, in what was likely a single proton. It was aptly named the "Oh-My-God particle".

andrewcooke 15y ago

it wasn't just religious nuts - i was worried myself (i may be a nut, but i am certainly not religious!) - and most people dismissing the worries on the internet were "science groupies" without a detailed understanding of the issues (in my experience, at the time, as far as i recall, etc). thankfully, there was a good report written that addressed the concerns in substantial detail. if you haven't read it, it's very interesting (and moderately reassuring) - http://cdsweb.cern.ch/record/613175/files/CERN-2003-001.pdf?version=1 http://cdsweb.cern.ch/record/613175/files/CERN-2003-001.pdf?... [ps an example of how simple arguments are not necessarily right is that any black hole created by the lhc would be almost at rest in the frame of the collider, unlike expected products from astronomical processes; that means that it would be gravitationally bound, allowing the effects of a small cross-section to accumulate over time. this isn't advanced physics, by any stretch of the imagination, yet people never seem to address it. another issue is that planets may indeed be destroyed by cosmic processes - at the time the lhc was being designed we had very little in the way of statistics on the number of planets or their lifetimes, outside of our own solar system.]

philipn 15y ago
Did you find an exploration of the gravitationally-bound black hole idea? I've been wondering the same thing since reading about this a few years ago.

Florin_Andrei 15y ago

No reason to worry as long as we're not matching Mother Nature yet in terms of energy. We're not even close. She's doing a lot more nasty things, even here on Earth, on a daily basis. Nothing's happened as a result. So we'll be fine.