A few hundred episodes ago, I answered the question, “What is the Universe Expanding Into?” The gist of the answer is that the Universe as we understand it, isn’t really expanding into anything.
If you go in any one direction long enough, you just return to your starting point. As the Universe expands, that journey takes longer, but there’s still nothing that it’s going into.
Okay, so, I need to put an asterisk on that answer, and then when you read the fine print it’d say something like, “unless we live in a multiverse”.
One of the super interesting and definitely way out there ideas is that our cosmos to actually just one universe in a vast multiverse. Each universe is sort of like a soap bubble embedded in the cosmic void of the multiverse, expanding from its own Big Bang.
And in each one of these universes, the laws of physics are completely different. There are actually a bunch of physical constants in the Universe, like the force of gravity or the binding strength of atoms. For each one of those basic constants, it’s as if the laws of physics randomly rolled the dice, and came up with our Universe – a place that’s almost, but not completely hostile to life.
So imagine all these different bubble universes popping up in this vast cosmic foam of the multiverse, and the laws of physics are different. Maybe in another universe, the force of gravity is repulsive, or green, or spawns unicorns.
In the vast majority of those universes, no life could ever form, but roll the dice an infinite number of times and you’ll eventually get the conditions for life.
Any lifeform capable of perceiving the Universe had to evolve into a universe capable of life.
Of course, this sounds like pseudo scientific mumbo jumbo, and next you’ll expect me to talk about chakras, astrology and channeling the spirit of Big Foot.
However, hang on a second, this might actually be science. If these bubble universes got close enough, there might be a way they could rub together, to interact in ways that were detectable from within the Universe.
In other words, we could look out into space and see a cosmic bruise, and know that’s where our universe is colliding with another one.
Well, have astronomers looked out into space, in search of some sign that our Universe is interacting with other universes? Indeed they have, and they’ve found something really strange.
When examining the Cosmic Microwave Background Radiation, the afterglow leftover from the Big Bang, astronomers have found a temperature fluctuations. These different temperatures, or anisotropies are regions where different densities of matter in the early Universe were scaled up to enormous scales by the ongoing expansion.
While most of these differences in temperature are explained by the current cosmological theories for the Universe, there’s one region that defies the theories. It’s so strange, the researchers who discovered it hilariously named it the “Axis of Evil” after something some president said.
Anyway, there are lots of ideas for what the Axis of Evil might be. Seriously, every single one of them is more reasonable and more likely than what I’m about to say.
But one really fascinating idea is that we’re seeing a region where our Universe is bumping into another universe, violating each other’s laws of physics.
So if this is the case, and astronomers are witnessing a universal interaction, what does this mean for the poor aliens who might be getting overlapped by the next universe over?
We have no idea, but imagine what might happen as the laws of physics from two completely different universes overlap. What is the average of 7 and green? Or 26 and unicorn dreams? Whatever it is, it can’t be good for the aliens and their continued healthy existence.
But don’t worry, that region is billions of light years away, and it’s probably not another universe anyway, we just need better observations.
We covered this topic in great detail in episode 408 of Astronomy Cast, so if you want hear more from Dr. Pamela Gay, click here and watch the show. You’ll especially enjoy watching me pick up the shattered pieces of my brain as I try to wrap my head around this mind bending concept.
and why not??!!
Hi PUNCHCARD4GTAC,
That question is what drives research, as well as natural human curiosity.
We have a long way to go to find the answers.
In other words, finding the cause of the distortion in the Cosmic Microwave Background Radiation arrears to me to be so difficult, that it will not be found in my lifetime.
I love this topic. I always try to think about what would “be” if our universe (or any universes as it may be), did not exist. What would “exist” if anything….and if nothing existed, how do we picture it..or, like a 4th or higher dimension, can we picture it? This is kinda the same questions as “what is out universe expanding into?”. For some reason this totally intrigues me……and for some crazy reason, if nothing existed, I picture infinite “yellow”.
Yes it is a multi-verse. In fact, an infinite multiverse. The individual universes emerge from the infinite stuff that surrounds them. Namely densely packed photons of all wavelengths and energies. Essentially the same stuff of black holes.
Our universe exists inside a cavitary bubble created by the shock wave of a singular event in a medium of significant density (non-particulate) that resulted from the resolution of a higher energy state to a lower energy state (an explosion as it were) in that medium not unlike Feynman’s solution for detonating the plutonium bomb (implosion{creates particulate matter}/explosion {creates the bubble}).
This medium? Densely packed photons, hnu, or energy The same stuff that not only makes up everything in our universe (all particles can eventually be reduced to their photons), but that which exists at the boundary of our cavitary bubble, and beyond, being responsible for the gravitational field into which everything is subsequently being drawn (calculate the resultant gravitational vectors inside of a hollow sphere in a large cube of very dense material). This material (densely packed photons), by the way, is the same stuff of black holes (particulate matter enters and is reduced to it’s constituent photons).
From electron positron interactions we know that only 2 511kev photons result. No particles. Electrons and positrons have mass and from the formula for conversion of mass and energy, Ta Da! so do photons (only while moving {no rest mass} which is going to be a hard one to measure given their speed and linear orientation through the Higgs field, however in a circular course {like around a black hole} their mass should be measurable)!
Imagine, packing electrons as tight as one may, actually touching one another, into a 10cc cube. Summing their gravitational components from their masses using the gravitational equation we would arrive at some number for this 10cc cube.
Now, since the electron is quite voluminous (as it contains only one photon, no other particles), imagine if the volume of the electron were to be reduced to the volume of it’s constituent photon.
What we end up with would be the same amount of gravitational content in a volume significantly smaller (infinitely smaller?) than our 10cc cube. Conversely, if we created a 10cc cube of this condensed electron constituent, we might even call it a baby black hole with all of the gravitational attributes of something so dense and concentrated.
Now scale the whole shebang from infinite to infinitesimal.
Finally, all of the constituents of our universe are accelerating, via gravity, to the edges of our universe due to a large amount of gravitationally significant material that exists at it’s margins (and further).
At some point in time the cavitary bubble will cease to expand and will then contract (could be happening now…).
Yet, we will continue to accelerate to the margins, under the gravitational pull (in our hollow, cavitary sphere), and ultimately merge with and into the stuff (energy, photons, hnu, however you’d like to define it) that exists there (which may also be occurring and may actually be responsible for some of the information gathered by COBE as some of our particulate matter gets consumed by the margins.).
The complete collapse of the cavitary bubble with our continued acceleration towards the margins will eventually result in the consumption and ultimate reduction of all matter back into their constituent photons and dissipation of the bubble probably back into another high energy state singularity as the margins crash into one another that requires resolution into a lower energy state via another cavitary, shock wave explosion.
So we live in a kind of baked bread multi-verse with all of the holes in the baked dough representing the many universes and the dough representing the stuff that lies between them all (densely packed photons) from which everything is made.
What would lie beyond the dough?
What would then lie beyond the dough?
Wow! You blew my mind but also gave me a something to hang my hat on.
Those several paragraphs succinctly explained a very complex and varied topic into a neat consistent picture of how the more obscure aspects of matter work. I especially liked the bread analogy.
I wonder, couldn’t we also consider the thermodynamic aspects? So, as matter is consumed, whether into photos at black holes, or via fusion or fission in solar bodies, etc., heat is produced along with photons. But this heat energy must have come from something, so would photon decay be the source of this energy? Also, where does this heat go at the peripheries?
So using the bread analogy, could we conjecture that as time progresses, as the bubbles collapse in the bread, the loaf becomes both hotter and smaller as the photon/hnu/whatever stuff gets consumed? It would seem that what you laid out, along with considerations for the source of heat energy, at least explains the many anomalies that have been observed. Of course, how to prove it?
So an answer is not really given. Let’s ask, what is beyond our observable Universe? It would be that part of our Universe that is speeding off faster than the speed of light. The true boundary of our Universe can’t be seen. Still, what is beyond that? Nothing? If so, is it the same kind of nothing that exists between galaxies, stars, planets and moons? Imagine an empty container. The space inside it is not nothing. It is that which is waiting to be filled with something, as of volume. True nothing can not exist. You can say our Universe is self contained and beyond it is the potential for something to exist. Perhaps other self contained multiverses. True nothing, the lack of a potential something to occupy a volume of space is truely a waste of a possible container of existence.
@fowlowl1955: The universe began as an infinitesimally small dimensionless point called a singularity and we observe this point to be located about 47.5 billion light years away in every direction in our 13.8 billion year-old universe. The continuous expansion of new time and space takes place entirely within the singularity – there is no such thing as an outside the singularity for spacetime to expand into.
To put it another way, a theoretical outside observer looking at our universe would only detect an infinitesimally small singularity (and even though there is no outside to our universe, there is no reason why an infinite number of singularities couldn’t exist; each with its own universe of continuously unfolding time and space within).
“Reality is merely an illusion, albeit a very persistent one.”
Albert Einstein, US (German-born) physicist (1879 – 1955)
So like bubbles we may pop or merge into a giant bubble. The laws of the universes fighting or joining together sending everything into a chaotic jumble till it all resettles into a new larger universe. Or.. Or… We pop and we like the soap bubble, release our contents into the open whatever you want to call it. Outerverse? Omniverse? Not sure of a good name for it.
Upon this bursting, everything will dissolve into the open air so to say. And in the open air our universes matter and energy etc will be at the mercy of whatever laws of the Outerverse inflict upon us. My question though would be, who or how did our buble get made to begin with?
Who captured our contents and put them in the bubble? A giant cosmic child girl blowing cosmic bubbles? Our existence nothing more than a few seconds in the view of this cosmic child?
“And in each one of these universes, the laws of physics are completely different.” Not actually true. (not that anyone could ever verify it). I’ve read Brian Greene.
This is no more than an exercise in mental masturbation by an impotent entity.
If so, what makes the entity “impotent?”
Then of course there’s the quantum physics answer, which is: The universe is basically made of thought-forms. What we perceive is what we create mentally. In other words we are all sort of projectors projecting our ideas of reality and these collective ideas actually make up the universe. So what happens when we get to the end? We just mock up something else and that is what will be. Whatever we “project” and agree upon will be the reality we perceive. I know it sounds far out, but no more far out that multi-universes, in my opinion.
Yeah, this is the one I like. You need observers in order to force infinite quantum possibilities into a single reality, fixed into place moment by moment, inadvertently creating time, perhaps. The narrative is only possible b/c of the observer(s),
This is no more than an exercise in mental masturbation by an impotent entity.
“Duplicate comment detected; it looks as though you’ve already said that!”
Not true. This is my first and only comment on this article. Your response is a lie because you didn’t like a comment I posted on another article.
Or maybe the background red shift is caused by photon energy loss, from absorption and re-emission, refraction, gravitational lensing, interference, dispersion, and even the Poynting-Robertson Effect if there is an infinitisimal mass associated with the photon (see Goldhaber, Alfred and Nieto, Michael, “The Mass of the Photon,” Scientific American, May 1976). Pair formation of 1.0216 MeV gammarays (“the creation operator”) should be adequate to populate the universe with matter given enough time, as the 13.8 billion year limit would not apply in this case.
@Tim: We observe that the CMBR itself is redshifted in one direction and blueshifted in the opposite direction, which indicates that our Local Group of galaxies moves at about 600 kilometers per second relative to the primordial radiation produced by the BB event.
Or maybe the background red shift is caused by photon energy loss, from absorption and re-emission, refraction, gravitational lensing, interference, dispersion, and even the Poynting-Robertson Effect if there is an infinitisimal mass associated with the photon. Pair formation of 1.0216 MeV gammarays (“the creation operator”) should be adequate to populate the universe with matter given enough time, as the 13.8 billion year limit would not apply in this case.
Or maybe the background red shift is caused by photon energy loss, from absorption and re-emission, refraction, gravitational lensing, interference, dispersion, and even the Poynting-Robertson Effect if there is an infinitisimal mass associated with the photon (see Goldhaber, Alfred and Nieto, Michael, “The Mass of the Photon,” Scientific American, May 1976).
Pair formation of 1.0216 MeV gammarays (“the creation operator”) should be adequate to populate the universe with matter given enough time, as the 13.8 billion year limit would not apply in this case.
Because the following comment was “already submitted” (supposedly) it is not being allowed. i hope Mr. Cain is not engaging in obscurantism in denying other descriptions of the background red shift. Comment: Or maybe the background red shift is caused by photon energy loss, from absorption and re-emission, refraction, gravitational lensing, interference, dispersion, and even the Poynting-Robertson Effect if there is an infinitisimal mass associated with the photon (see Goldhaber, Alfred and Nieto, Michael, “The Mass of the Photon,” Scientific American, May 1976). Pair formation of 1.0216 MeV gammarays (“the creation operator”) should be adequate to populate the universe with matter given enough time, as the 13.8 billion year limit would not apply in this case.
Because my comment was “already submitted” (supposedly) it is not being allowed. I hope Mr. Cain is not engaging in obscurantism in denying other descriptions of the background red shift.
Because my comment was “already submitted” (supposedly) it is not being allowed. I hope Mr. Cain is not engaging in obscurantism in denying other descriptions of the background red shift. Comment: Or maybe the background red shift is caused by photon energy loss, from absorption and re-emission, refraction, gravitational lensing, interference, dispersion, and even the Poynting-Robertson Effect if there is an infinitisimal mass associated with the photon (see Goldhaber, Alfred and Nieto, Michael, “The Mass of the Photon,” Scientific American, May
1976). Pair formation of 1.0216 MeV gammarays (“the creation operator”) should be adequate to populate the universe with matter given enough time, as the 13.8 billion year limit would not apply in this case.
This comment section is “fixed’ worse than the GOP nominating process.
“If you go in any one direction long enough, you just return to your starting point.”
This only really applies if the universe has a closed, finite geometry (in at least one direction). It may just as easily be infinite in extent; we can’t really tell.
I’m no expert, but it seems to me this is mistakenly, and somewhat haphazardly blending many aspects of physics which is an impossible no no. “Uni” basically means one or all encompassing. “Multi” implies multiple forms, layers, etc. We either live in a Universe, or we live in a Multi-verse.
All rules concerning the Universe are governed by the laws and theories of Issac Newton, and Albert Einstein for the most part. Or the Macroscopic environment. Whereas Multiverse Theory is by and large related to the many worlds theory of Quantum Physics.
Even in the many worlds theory, Heisenberg’s Uncertainty Principle is in effect.
It goes on later to blend in the idea of the Anthropic Principle I believe it’s called that basically says that conditions for life to exist must be present for life to be present. So that’s a given, but it’s also a philosophical and subjective opinion, because frankly we still don’t know what could exactly qualify as life.
Then he bends back to the CMB, and that’s back into the macroscopic again. Kind of a haphazard brain fart on the star ship WOW. Makes me think the author was celebrating 420 day. JS
@Mr Whizard: Our universe is enclosed within a singularity, an infinitesimally small dimensionless point. Although there is no such concept as an outside to our singularity universe, there is no reason why an infinite number of singularities couldn’t exist; each with its own universe of infinite energy dissolving into static mass and continuously unfolding new time and space within.
“Reality is merely an illusion, albeit a very persistent one.”
Albert Einstein, US (German-born) physicist (1879 – 1955)
“If you go in any one direction long enough, you just return to your starting point”
My understanding is that this has to do with the three dimensional geometry of the universe. I thought the current thinking is that the geometry of the universe was not spherical and that parallel lines diverge to infinity, so the idea that if you go far enough you end up where you stated from was an old fashion idea. I thought the current thinking is that we lived in a double saddle universe I forget the term for that geometry. It is easier to comprehend ending up where you started from but you don’t. At the same time is true that there is nothing beyond the end of the universe. It is finite. I guess isn’t what is beyond the universe the fourth or fifth dimension? This is much harder to visualize then that you end up where you started from.
@Jond: I completely agree that the quote “If you go in any one direction long enough, you just return to your starting point” is false and archaic. I question why someone would include it in a current cosmology article. I believe there is a finite or “Collapsing universe” model which shows this statement to be true, but we don’t observe enough mass or gravity within the universe to close it, so the model hasn’t achieved wide acceptance.
Curiously enough, Einstein’s ToR shows us that no matter where you go, or how fast you travel to get there, you must always maintain your relative frame of reference of viewing yourself at the center of the universe. Maybe the quote should be updated to read: “If you go in one direction long enough, you just remain at your starting point”.
“The universe is not required to be in perfect harmony with human ambition.”
– Carl Sagan, US astronomer & popularizer of astronomy (1934 – 1996)
What is outside the Universe? This is a mis-framed question akin to “what is outside the box?”
First, you have to have a box. THEN you can define an “inside” and an “outside”. The inside and outside are not “parts” of the box, anymore than space and time are “parts” of the Universe. We understand some of the PROPERTIES of space and time but we don’t really know how to DEFINE them.
This is like a problem with real numbers. We know how to use them (add, subtract, multiply divide, etc) but their DEFINITION is actually kind of complicated; mathematically they are defined in terms of Cauchy sequences or Dedekind cuts. But this is a question most people don’t even think about, like the question of “Why is there a horizon?”
What IS space? What IS time? All I can offer is a hint from Einstein. He said that “without motion, nothing happens”. So take motion as the box, and then define space and time in terms of derived properties of motion.
That leads to the question of “What kind of motion produces (defines) what kind of space or time?” That may sound kind of silly, but you are already familiar with one aspect of this: motion at very high speeds slows down the passage of time.
There is also something called “non-local motion”. Where do things go when there is no “where” to go to? The EPR paradox is an example.
Clearly the question of “What is outside the Universe?” involves deep questions about space and time themselves. For further insights I recommend the paper: “Beyond Einstein: Non-local physics” by Brian Fraser (2015). The .html file gives a link to the .pdf, and also contains additional information such as updates and comments.