Ask Me Anything AMA with Astrophysicist Dr. Joe Pesce!

Page 2 - For the science geek in everyone, Live Science breaks down the stories behind the most interesting news and photos on the Internet.
Status
Not open for further replies.

DrJoePesce

Verified Expert
Mar 27, 2020
24
36
60
What are your thought on gravitons ? Why is there the thought that the mechanism of gravity would work via particles ? Also hypothetically, if an immense black hole just 'popped' into existence 4 light years away from me, would the gravity of the black hole take 4 years to affect me ? or would the effect be instantaneous with the appearance of the black hole? Is there any experimental evidence of the 4 year or /instantaneous effect?
Hi ediso74, thanks for the question. Gravitons are the modulators of the gravitational force just as photons are the modulators of the electromagnetic force. Theory predicts that gravitons travel at the speed of light (they can’t travel faster; they could travel more slowly); and observations of gravitational waves by NSF’s Laser Interferometer Gravitational-Wave Observatory (LIGO) are consistent with gravitons moving at the speed of light.

Yes, if a black hole suddenly appeared four light years away it would take four years.
 
  • Like
Reactions: jchamot
Jan 13, 2020
23
4
35
In responding to a post, I got to thinking about things I would like to know more about in astrophysics. We know a lot about a lot of things in astronomy – much more than when I was a graduate student long ago. And it seems like not a day goes by without a new, neat, astronomical observation making the news. And keep an eye and ear open: NSF’s newest astronomical facilities – the Daniel K Inouye Solar Telescope and the Vera C. Rubin Observatory – will soon be coming online, and they promise some truly spectacular (game changing) science. Even given this, astronomy is very much still in discovery space: new observations lead to completely unexpected findings all the time.

Of course, I’m a scientist, so I want to know everything! But let me try to narrow it down to a random (short) list of neat things I’d like to see:
  • What’s driving the solar cycle
  • What are Fast Radio Bursts
  • Is there extraterrestrial life
  • What is Dark Matter
  • What is Dark Energy
  • More info about supernovae
  • How do galaxies form
  • Why are there different types of galaxies
  • What happened immediately after the Big Bang
  • How do supermassive black holes form and grow
  • What are AGN
  • How do AGN jets remain powered for such large distances and long times
  • How do stars and planets form
  • Is there a unified model at work in the universe
  • Are the laws of nature truly universal in space and time
  • What will happen to the universe in the deep future
  • What is happening in the quantum realm
  • What happens inside the event horizon of a black hole
You're probably a tad busy but there's a whole heap of stuff on plasma, magnetic and electric universe, solar micronova, galactic sheet and pole flip stuff here. I've been following this for a about a year now, only as a layperson, but a huge amount of work has been done and there is a serious scholarly approach in place, albeit very challenging. Not for the fainthearted. https://www.observatoryproject.com/weathermans-guide.html and https://suspicious0bservers.org/
 
  • Like
Reactions: jchamot
Dec 23, 2019
325
21
205
Can you give me your thoughts on the Holographic Principle? Don't you think it has credence coming from Susskind?

How do the holograms in the Holographic Principle follow the rules of Physics?

You mentioned blazars, so I have to ask if you think they are beaming quantum information at us. I have an admittedly insane idea that our consciousness could be in that information.

What if I told you that it doesn't matter that everything is accounted for after annihilation? Once decoherence assigns quantum gravity, it can't be transferred to the product of annihilation. You end up with gravity that isn't assigned to matter and is apparently more potent because of it ..aka Dark Matter.

If quantum information describes a particle, could gravity be another variable? Is quantum gravity somehow different from other quantum information?

Does spacetime have a quantum gravity memory? Is matter holographic, but gravity is assigned another way? Is the Holographic Principle only good for converting quantum information to physical matter via wave collapse? Everything else is left to spacetime to handle physics?
 
Last edited:
Sep 3, 2020
5
0
30
Hi Dr. Pesce. Do you think it's possible the solar system has a different purpose than we've been taught? Do you know of any hard evidence to fundamentally break this idea:


Thank you.

--
Rick C. Hodgin
 
Jan 13, 2020
23
4
35
You're probably a tad busy but there's a whole heap of stuff on plasma, magnetic and electric universe, solar micronova, galactic sheet and pole flip stuff here. I've been following this for a about a year now, only as a layperson, but a huge amount of work has been done and there is a serious scholarly approach in place, albeit very challenging. Not for the fainthearted. https://www.observatoryproject.com/weathermans-guide.html and https://suspicious0bservers.org/
and here
View: https://www.youtube.com/watch?time_continue=98&v=e-YnnPN6Rts&feature=emb_logo
 
  • Like
Reactions: jchamot

DrJoePesce

Verified Expert
Mar 27, 2020
24
36
60
Wouldn't a Neutron Star give us a snapshot of a Black Hole before it is born?
Hi pittsburghjoe (great name btw!),

Certainly a supernova (exploding massive star) can – when it collapses - create a neutron star, a black hole, or blow itself completely apart. So, when the core collapses on its way to becoming a black hole, matter gets very dense (and then infinitely dense in the black hole singularity), so there may be a neutron-star-like phase. But this collapse happens so rapidly (~ 1/2 second) that it’s probably not a valid way to look at the process. I’m also not sure if the collapsing core converts to neutrons before it becomes a black hole. Maybe, but probably not.
 
  • Like
Reactions: Sally and jchamot

DrJoePesce

Verified Expert
Mar 27, 2020
24
36
60
You're probably a tad busy but there's a whole heap of stuff on plasma, magnetic and electric universe, solar micronova, galactic sheet and pole flip stuff here. I've been following this for a about a year now, only as a layperson, but a huge amount of work has been done and there is a serious scholarly approach in place, albeit very challenging. Not for the fainthearted. https://www.observatoryproject.com/weathermans-guide.html and https://suspicious0bservers.org/

Thanks Sally! Oh yes, there are many many more (many) things I could have added to my list…. ☺
 
  • Like
Reactions: Sally and jchamot
Dec 23, 2019
325
21
205
Is the CMB or quantum fluctuations the entropy of our Holographic Principle?

Is the difference between a parent Black Hole and ours the fact that the parent Black Hole has Spacetime in it?
 
Last edited:

DrJoePesce

Verified Expert
Mar 27, 2020
24
36
60
We’ve seen in this session (and elsewhere, of course), many ideas about how the universe and nature works. These are great: It’s curiosity that drives science. And there are many ways of looking at and thinking about the universe. All ways of looking and thinking about these things are valid. Science focuses on looking and thinking about the universe using the principle of testability, where data are obtained and compared to predictions made by our guesses at how things work (hypotheses), where independent groups of scientists study the same phenomenon (sometimes with different instruments) and then compare results, and where we try to refute these initial guesses.
  • If the hypotheses resist being refuted, then we gain confidence that they are closer to explaining the underlying phenomenon
  • If predictions (made before the observation or experiment) match what we expect from the hypotheses, then the hypotheses are close to explaining the underlying phenomenon
  • If predictions do NOT match the hypotheses, then we’ve guessed incorrectly, need to tweak the initial guess, or our underlying understanding is incorrect
  • If observations (or experiments) made of the same phenomenon by independent groups don’t agree, there is something wrong: With the hypotheses, with the experimental setup, with the instruments, with our underlying understanding, etc.
And we need to apply Occam’s Razor liberally: If my hypothesis explains a phenomenon well but requires 100 assumptions to be valid, and yours explains the situation equally well but only requires one assumption, then – for the time being – we will go with your hypothesis (but not forgetting mine). In the end, maybe my hypothesis IS correct, but I usually find that the simple explanations are more often correct.

Science is much more complex than this, but as a high-level summary this is fundamentally what is happening. If we can’t test our hypotheses, then we can’t gain a better/deeper understanding of the phenomenon we are trying to study (and, fundamentally, we wouldn’t call that process “science”).

It’s important to note that our understanding of nature is constantly changing, because we only have an incomplete view (in general). Scientists don’t like to be wrong (we are human after all) but we are open to being wrong – its how progress is made.
 
Feb 28, 2020
23
10
35
Hi, yet again DrJoe Pesce,

Thanks once more for your last great reply.

I was going to ask you what your favourite or preferred universe theory was, but in your last reply to me you said;

"In the far distant future, expansion will have an affect even on the smallest scales, and atomic nuclei, for example, will be pulled apart by the expansion."

So, can I assume you favour the 'big rip'?

I was in a thread trying to convince someone there wasn't going to be a heat death. I'll paste my post here and I'd like your opinion please;
https://forums.space.com/threads/scientist-calculates-the-sad-lonely-end-of-the-universe.33019/ Post 24;

"The observation of the accelerating expansion of the universe is explained with dark energy. We don't know what dark energy is or its full properties. Your support for the end of the universe is dependent on something we know nothing about or even if it exists at all. Don't you think that something as important as the end needs something a bit more concrete than an unknown 'dark energy'?

Anyway, what do you mean by 'the universe'?

The dictionary definition of 'universe' is "everything that there is". You, this web sites articles and most top scientists seem to keep referring to the big bang and the universe as one and the same thing. For example, statements like - "The universe started with the big bang". It is a huge assumption that the contents of the big bang are 'everything that is' ie the universe. There's absolutely no evidence to support this, I find it completely unscientific.

So until proven otherwise, I think it's equally good (no, better) to assume the universe is infinite and contains infinite 'stuff'. Meaning the contents of the Big bang is not 'everything that is' ie the universe. With this in mind, the contents of the big bang are expanding into the stuff of rest of 'The Infinite', as I like to call it. When it hits this 'stuff', the 2nd law will not be able to expand the contents of our big bang anymore. So no heat death!

Everything that exists, exists in a space. The big bang may have created space (space itself being a 'something' eg quantum foam etc), but at the same time, it must have existed in a space, even if just a void or geometric space. So, if you want to stick with the idea that the contents of the big bang is also the universe, you are assuming that the rest of space that the big bang existed in is infinite and void, in order to allow indefinite expansion and heat death. A bit absurd in my opinion.

Me from last post - "For something to have a beginning, it must be a part of a greater whole or from something pre-existing, otherwise, it's just another something from nothing theory." Again with this proposition, the contents of our big bang are expanding into the greater whole, and so can't expand forever - no heat death.

Altogether, with unknown dark energy, and the possibility that the contents of the big bang are expanding into a 'greater whole' or 'The Infinite', don't you think it's a bit unsafe to predict the end, (heat death) of 'everything that there is' just yet? :)"


To summarise;

Matter/energy can't be created or destroyed, so no beginning or end, something has always existed, including before our big bang. All theories about universes must have a cyclic or recycling property to them. So, we are partway through the current cycle of a big bang among, IMO, an infinite number other big bangs.

Existence is eternal. The proof is we are here, surrounded by matter and order, because no process has ever destroyed it. Including black holes or heat deaths in previous big bang contents. Order even survived coming through our Big Bang. Order can't be created or destroyed. This all goes to show that one day all that went into black holes will come out again, both matter and order.

Everything that exists, exists in a space, including the contents of the Big bang IMO. The big bang may have created its own space (space itself being a 'something' eg quantum foam etc), but why can't this created space also exist in a space at the same time?

Thank you :)
 
  • Like
Reactions: Sally and jchamot
Dec 23, 2019
325
21
205
I don't have a degree in physics, it takes someone like you to not be dismissive and actually consider what I'm saying.

I completed the Unified Theory with the Holographic Principle.

Black Holes are eating holograms. The quantum information is safe out at the edge of our universe. Dark Matter is annihilated holograms, again the quantum information isn't anywhere near the event.

Projected quantum information rides on the fabric of spacetime. When it isn't decohered ..it is the unobservable side of QM.

Does projected quantum information become physical Spacetime objects with wave collapse?

The Holographic Principle projects holograms that are from quantum information. Spacetime takes these instructions and generates/mirrors physical objects.
 
Last edited:
  • Like
Reactions: Sally
Jan 13, 2020
23
4
35
Yes, I would like to see verification of this result. But, certainly, we already know the expansion rate can change: That’s the core of Dark Energy, which seems to have caused the expansion rate to increase some billion years ago or so.
I wonder how many life species (sentient or otherwise) could have been and gone in a billion years :~)
 
Jan 13, 2020
23
4
35
Hi, yet again DrJoe Pesce,

Thanks once more for your last great reply.

I was going to ask you what your favourite or preferred universe theory was, but in your last reply to me you said;

"In the far distant future, expansion will have an affect even on the smallest scales, and atomic nuclei, for example, will be pulled apart by the expansion."

So, can I assume you favour the 'big rip'?

I was in a thread trying to convince someone there wasn't going to be a heat death. I'll paste my post here and I'd like your opinion please;
https://forums.space.com/threads/scientist-calculates-the-sad-lonely-end-of-the-universe.33019/ Post 24;

"The observation of the accelerating expansion of the universe is explained with dark energy. We don't know what dark energy is or its full properties. Your support for the end of the universe is dependent on something we know nothing about or even if it exists at all. Don't you think that something as important as the end needs something a bit more concrete than an unknown 'dark energy'?

Anyway, what do you mean by 'the universe'?

The dictionary definition of 'universe' is "everything that there is". You, this web sites articles and most top scientists seem to keep referring to the big bang and the universe as one and the same thing. For example, statements like - "The universe started with the big bang". It is a huge assumption that the contents of the big bang are 'everything that is' ie the universe. There's absolutely no evidence to support this, I find it completely unscientific.

So until proven otherwise, I think it's equally good (no, better) to assume the universe is infinite and contains infinite 'stuff'. Meaning the contents of the Big bang is not 'everything that is' ie the universe. With this in mind, the contents of the big bang are expanding into the stuff of rest of 'The Infinite', as I like to call it. When it hits this 'stuff', the 2nd law will not be able to expand the contents of our big bang anymore. So no heat death!

Everything that exists, exists in a space. The big bang may have created space (space itself being a 'something' eg quantum foam etc), but at the same time, it must have existed in a space, even if just a void or geometric space. So, if you want to stick with the idea that the contents of the big bang is also the universe, you are assuming that the rest of space that the big bang existed in is infinite and void, in order to allow indefinite expansion and heat death. A bit absurd in my opinion.

Me from last post - "For something to have a beginning, it must be a part of a greater whole or from something pre-existing, otherwise, it's just another something from nothing theory." Again with this proposition, the contents of our big bang are expanding into the greater whole, and so can't expand forever - no heat death.

Altogether, with unknown dark energy, and the possibility that the contents of the big bang are expanding into a 'greater whole' or 'The Infinite', don't you think it's a bit unsafe to predict the end, (heat death) of 'everything that there is' just yet? :)"


To summarise;

Matter/energy can't be created or destroyed, so no beginning or end, something has always existed, including before our big bang. All theories about universes must have a cyclic or recycling property to them. So, we are partway through the current cycle of a big bang among, IMO, an infinite number other big bangs.

Existence is eternal. The proof is we are here, surrounded by matter and order, because no process has ever destroyed it. Including black holes or heat deaths in previous big bang contents. Order even survived coming through our Big Bang. Order can't be created or destroyed. This all goes to show that one day all that went into black holes will come out again, both matter and order.

Everything that exists, exists in a space, including the contents of the Big bang IMO. The big bang may have created its own space (space itself being a 'something' eg quantum foam etc), but why can't this created space also exist in a space at the same time?

Thank you :)
Sounds like you might enjoy a session of Doug Vogt (information universe) videos? http://dieholdfoundation.com/
 
  • Like
Reactions: David J Franks
Sep 3, 2020
17
1
30
one idea that keeps coming to my mind when I think of a black holes and light holes. This image keeps popping out at me. A black hole could be zipping towards us faster then the speed of light meaning the particles coming off the surface of the black hole might not even leave the surface . Think of it with this in mind what if you are an observer to the same black hole but on the opposite side it would be a light hole. Gamma Ray's coming off are
 
Sep 3, 2020
17
1
30
What are your thought on gravitons ? Why is there the thought that the mechanism of gravity would work via particles ? Also hypothetically, if an immense black hole just 'popped' into existence 4 light years away from me, would the gravity of the black hole take 4 years to affect me ? or would the effect be instantaneous with the appearance of the black hole? Is there any experimental evidence of the 4 year or /instantaneous effect?
When I think of gravitons . I think light would take that long to reach you only because the space time was rippled from the appearance of the black hole. A bunch of ups and downs the light would have to travel. If there was no ripples it wouldn't take light that long to get to you. It's not unreasonable to think it would happen instantly. Put simply there has to be a plain for the light to travel in the first place
 
Sep 3, 2020
17
1
30
Would it be to far fetched to think the reason we see the universe expanding when we look a long ways out is because we see it as it was a long time ago(inflation). In the far past it was moving that fast . But when we see stuff closer it slows down. The galaxies might no longer be there if we could instantaneously appear closer to the 13.4 billion light years away galaxies. One more thing if speeds could change and stuff could move faster then light would it be possible to be able to see the same galaxy at different stages of its growth in different spots of the universe at the same time and think it was different galaxies?
 

DrJoePesce

Verified Expert
Mar 27, 2020
24
36
60
Is the CMB or quantum fluctuations the entropy of our Holographic Principle?

Is the difference between a parent Black Hole and ours the fact that the parent Black Hole has Spacetime in it?
We can’t know what happens within the event horizon of a black hole, so we can’t say whether or not spacetime exists inside. All we know for certain is that there is mass.
 
Dec 23, 2019
325
21
205
Projected quantum information (entropy) is at the event horizon. I'm not sure if the mass is a product of spacetime or the quantum information.

Think about quantum tunneling. A particle with mass is able to tunnel but not when it is decohered. It became a spacetime object after the barrier.
 
Last edited:
Feb 28, 2020
23
10
35
Hello Again David J Franks!

So, an explosion isn’t really a perfect analogy, but it’s okay. It’s just that most of the energy of the Big Bang goes into the expansion of the universe – space, as you say. That expansion – on the large scale – is overwhelming. And while individual galaxies and objects embedded in space can move independently of the cosmic expansion (for example our Milky Way galaxy and the Andromeda galaxy are falling into each other), the expansion will win in the end. In the far distant future, expansion will have an affect even on the smallest scales, and atomic nuclei, for example, will be pulled apart by the expansion.

One reason the explosion analogy doesn’t, fully, work, is because SPACE is expanding (imagine the rubber sheet stretching). In an explosion, while a gas might be expanding (for example), that’s not the same thing as the medium in which everything is embedded is itself expanding.
One reason the explosion analogy doesn’t, fully, work, is because SPACE is expanding (imagine the rubber sheet stretching). In an explosion, while a gas might be expanding (for example), that’s not the same thing as the medium in which everything is embedded is itself expanding.
Hi, again, DrJoe Pesce

I'm assuming space is a 'something' just as gas is.

SPACE is expanding, with embedded galaxies
GAS is expanding, with embedded ball bearings

Space is pushing the galaxies apart.
Gas is pushing the ball bearings apart.

To compare like with like, I've assumed the big bang happened from a finite size in a pre-existing space.

I still can't see any difference.

After rewording my analogy is your answer still the same? :)
 

DrJoePesce

Verified Expert
Mar 27, 2020
24
36
60
one idea that keeps coming to my mind when I think of a black holes and light holes. This image keeps popping out at me. A black hole could be zipping towards us faster then the speed of light meaning the particles coming off the surface of the black hole might not even leave the surface . Think of it with this in mind what if you are an observer to the same black hole but on the opposite side it would be a light hole. Gamma Ray's coming off are
Hello ThinkTank, I love the thinking! First of all, you mention “light holes”. I’m not sure what you mean, but presumably “white holes”. While we have lots of evidence for black holes, we don’t have any for white holes. They can, theoretically, exist, but we’ve not detected any. Ah, and reading further I see what you are suggesting for “light holes”. Remember, black holes have mass, so they can’t travel faster than the speed of light.
 

DrJoePesce

Verified Expert
Mar 27, 2020
24
36
60
Would it be to far fetched to think the reason we see the universe expanding when we look a long ways out is because we see it as it was a long time ago(inflation). In the far past it was moving that fast . But when we see stuff closer it slows down. The galaxies might no longer be there if we could instantaneously appear closer to the 13.4 billion light years away galaxies. One more thing if speeds could change and stuff could move faster then light would it be possible to be able to see the same galaxy at different stages of its growth in different spots of the universe at the same time and think it was different galaxies?
We DO see galaxies a long way away as they were a long time ago. In fact, EVERYTHING we observe in astronomy is as it was in the past (because of the finite light travel time). On a very local scale (for example our Milky Way galaxy and the Andromeda galaxy) gravity can affect galaxies more than the cosmic expansion, so they can move around each other, be attracted to each other, etc. But on the much larger scale, the expansion can’t slow down. The only way it could is if there were enough matter in the universe to slow expansion. If there were even more matter, then the expansion could stop, or even reverse. As far as we can tell, there is NOT enough matter in the universe to slow, stop, and/or reverse expansion.
 
Status
Not open for further replies.

ASK THE COMMUNITY