The Story of Our Universe May Be Starting to Unravel

That is pretty close to what the Everettian interpretation of the Schrodinger equation states, with that equation being the main statement of quantum mechanics.

But, there are other interpretations, such as Copenhagen, which roughly describes the various versions of string theory. There, extra elements are added that essentially meet the Schrodinger equation without accepting multiple worlds.

I don't know what all Hawking said about the various theories. He certainly had a lot to say.

I don't believe Hawking said anything serious that was also arbitrary.

And, I strongly suggest that anything Hawking said about physics, including QM deserves serious thought.

The thing about multiple worlds is that the equation that has been tested so strongly as to be the center of quantum field theory, the Schrodinger equation, may be directly interpreted as stating multiple worlds. Theory has to be devised to try to DODGE that fact.

I'd suggest reading the following as a relatively short and reasonably clear description"
https://en.wikipedia.org/wiki/Many-worlds_interpretation

This solves "spooky action at a distance" with no assault on known physics, such as the cosmic speed limit.

It's a nicely clean solution to the Schrodinger's cat problem, Wigner's Friend, etc.

It's jarring to think of multiple worlds, but let's face it - quantum field theory has well tested features that just aren't like the macro world we're used to.

 

STOP right there! You cannot be serious, talking about all these things, other than my direct question, after you had asked me:

WillReadmore said: ↑
...
Can you please just ask the question?

Did you not mean to imply, that if I just asked, that you would JUST ANSWER IT? As my previously animated, and clearly annoyed, recent reply made quite clear: my question has nothing to do with differing interpretations of Schrodinger, or with every G.D. thing that Hawking ever f'ing wrote or said, on the subject. I'm sorry-- was that not apparent to your "superior" intellect's comprehension, when I'd very ambiguously said:

DEFinning said: ↑
...You insert all kinds of additions into my question, such as saying that you don't know what I think of Hawking's ideas!...Or did you think I was asking something about my opinion on "Hawking's many statements about the various multiverse ideas." Where are you pulling that crap from?...I asked a freakin' simple question. Maybe you don't remember, but the reason you were writing a reply to me, about multiverse theories (& Schrodinger, and other things), was because I had mentioned it, in my story about Hawking. That is the only f'ing thing I'm asking about.
<End post snip>

Still unclear, when I followed that post with my most recent one, which you'd quoted, in which I went over the Hawking story?

DEFinning said: ↑
I had thought of as ridiculous, when I heard Stephen Hawking talk about it as fact, on his t.v. program How to think like a GENIUS-- that any time one makes a decision, a new universe automatically comes into being, a splinter of this one, in which the person had not made that decision, had acted differently-- (and not) treated as more of just a science fiction idea. So it's funny, that Hawking could put forth tripe-science, and not lose any of his credibility, amongst the believers in Sciencism; yet, more credible theories, though without the official stamp of approval from conventional theoretical science-- like that of external genetic modification of our ancestors-- just get dismissed out of hand by these same, who tend to be googley-eyed at the, "brilliance," of all of Hawking's ideas. It really is indicative of a partisan or, more accurately, a denominational way of, "thinking."
<End, internal post Snip>

As well as:

<Snip>
So your answer to my post #21, in which you say that Hawking did not have a "casual" attitude about such things, was mistaken. He had stated, as a fact, with no equivocation whatsoever, that every time any of us makes a decision, a whole new universe is created in which the "you" there, instead, makes some other decision. Clearly, this is a highly speculative notion, which we would be at an utter loss, in trying to explain its foundational mechanics, and yet Hawking embraced the concept, in a declarative sentence, as if there was not the slightest doubt, of this reality.
<End Snip>

How many times do I have to state the same thing, in order for you to understand my meaning? This is really your last chance, if that is not clear to you, WTF I'm referring to. See the two, almost identical explanations, above, in large, bolded print. I don't understand, then, why you are beginning your answer, with Everettian and Copenhagen interpretations-- is it not obvious that this is all irrelevant to my question? Do you have a problem, perhaps, with your eyesight? Shall I see if Moolk is willing to try to explain this to you?

But wait, I'd provided further clarification (pay special attention to the colorized print):

<Snip>
So, now do you agree, that he had be showing an arbitrary, subjective elevating of a particular theory, to a much higher level of credibility than it was entitled? It would be foolish, IMO, if he'd acted this way, in this case of multiverse theory, to believe that he would not likely have other "pet" theories, which he invests with much more credibility, than they'd be due, strictly on a basis of empirical science. By the exact same vehicle, personal tastes, do many scientists dismiss, out of hand, the things I had mentioned, earlier-- UAPs, Ancient Alien theory, even theories of a spiritual "dimension"-- all of which, have at least (equal), if not more, basis, than does this idea of instantly created universes. Do you agree? So my point was that it is inconsistent, and unscientific, to treat the multiverse theory, as depicted by Hawking, as any more credible than those other theories.
<End Snip>


That is all I have been asking. Now that I have stated Hawking's comments, and his attitude of presenting those comments as fact-- was that not, in your opinion, a respected scientist, treating as true, what is clearly an unproven theory? You will have to take my word, on the part about his presenting this way, unless you want to go watch the show yourself-- which you probably could do. I think it was episode #4, about time travel. It opens with what is supposed to be a Medieval scene, with candles lighting, and moving on their own, and so forth, which is where he makes fun of the simple folk of old, who would believe in something like magic, with no understanding of what they were seeing. And he ends his show, by doing the exact same thing, except about a "scientific" theory, as if that changes anything.

That had been my point about objectivity, and keeping the same standard, always. If you want to treat an very speculative idea like this, about instant universes, as credible, you have no foundation for dismissing talk of UFOs, or Ancient Alien Theory, or even Spiritual entities, or Bigfoot, for that matter, as unworthy of scientific consideration. I'm not saying that one needs embrace all those theories-- to each, their own. But if one is going to be a snob about empirical evidence, then they should apply equally, and consistently. I say, in the instance I have clearly related to you, Hawking was not doing that. DO YOU AGREE? Please answer this question, if you are cognitively capable of it.

 

As I've mentioned, I'll comment on Hawking if you cite something he said. If I see something he said that appears to be of interest here, I will contribute that.


Physicists have tested QM, and it's foundational Schrodinger equation for DECADES. QM is not a "I assume there are aliens" type of thing. It's more a tested foundation of the way the universe works at the particle scale. Once that is accepted, an individual must consider the further implications of the Schrodinger equation. And, every interpretation has elements that are not similar to what we experience in the macro world - including multiple worlds, entanglement, Schrodinger's paradox, etc.

There is nothing like that in UFOlogy. UFOlogy is all assumptions build on stories related by humans. There is no testing, no concrete, no theoretical principle, no solution to obvious questions, etc.

 

You are hopeless-- I told you what he said. Now, many times. WTH, here's one more, in parting: Hawking said that anytime we make a decision, a new universe is spawned, like this one, except in which that person makes, instead, a different decision. Since that is too far over your head, to comprehend; or because you are such a debater, that you don't dare answer, because you know that your argument is a loser, and you can think of nothing to say; therefore you will waste everyone's time, dancing around, not engaging my point, but also avoiding admitting its validity-- my making of said point (in post #21) having been enough to send you off on a divorced from reality tangent, of numerous posts, addressed to me, yet arguing against, to all appearances, someone saying that we should ditch our established scientific principles when, in truth, I had not even suggested the discarding of our highly theoretical ones. My argument (for anyone whose understanding of things, is grounded in reality), had been that we should signify, in our language, the differences in the strengths of empirical evidence, between our scientific understandings, when we speak about them. This is as simple a thing as, in the example I'd used from Will Readmore's post-- in which he'd definitively claimed that nothing, not even thought, can move faster than the speed of light-- adding the words "we believe," or "we know of" or anything along those lines, rather than stating it as an absolute fact, which our insufficient basis, makes seem a misleadingly rock solid understanding, rather than a theory which, granted, to this point, we've yet to find exception to. That is, however, the equivalent of making an absolute statement about the life in our oceans, from investigations that have not plumbed beyond 100 feet in depth. Again, to the sane thinking crowd, it will be clear that this has nothing to do with "discarding" anything.

As for you, Will, if that is your maximum mental capacity, after the inordinate amount of effort from me, to clear up your questions, that you could find in none of my posts, anything that Hawking had said, then I am not going to invest my time & effort to become apprised of your other "insights." I wish you well, but please do not expect me to take any of your posts seriously enough to invest the time in reading them, or in even composing a response, as if I could expect you to grasp that, either.

 

OK, you seem to be claiming that Hawking gave some level of support to the Everettian model of quantum mechanics, though you don't cite your source.

Quantum mechanics has been tested to show that it works. However, there are a number of models of how it works, and they are still in the range of theoretical physics. For instance there are a number of attempts at the Copenhagen model (which includes the string theories) and there is the Everettian model. Theoretical physicists have varying levels of confidence in these and have opinions on what approach might be more fruitful to explore.

The rest of the issue is that quantum mechanics is tested, giving confidence that it works and these further models are essentially mathematical explorations of how it works. I barked, because this is not like UFOlogy.

I agree that the terminology is somewhat confusing in how it communicates confidence. I doubt anyone is going to attempt to fix that. Since "theory" is in popular parlance, I would guess that science would have to stop using that word!

 

My source was me: I watched the program. That is why I had said:

You will have to take my word, on the part about his presenting it this way, unless you want to go watch the show yourself-- which you probably could do. I think it was episode #4, (about time travel?). It opens with what is supposed to be a Medieval scene, with candles lighting, and moving on their own, and so forth, which is where he makes fun of the simple folk of old, who would believe in something like magic, with no understanding of what they were seeing. And he ends his show, by doing the exact same thing, except about a "scientific" theory, as if that changes anything.
<End>

So you could watch the program, or trust my description, or you could couch your reply in caveat, such as: If Hawking had really depicted this, the way that you describe-- as if it were not at all theoretical, but rather, a fact-- then...
As you are so comfortable with dealing in science theoreticals, I don't know why you have trouble understanding that you could treat my assurance, if you don't trust it, in the same manner: as making your answer conditioned upon my description being accurate.

Related question, how would you, personally, classify this idea, AS I HAD RELATED that it had been expressed-- that the mere making of a choice, by anyone, causes a new universe to spring into being. Is that credible science?

 

Yes, you'll have to accept that your statement of Hawking's statement has a level of indirection that raises serious problems. For example, it includes no indications of context or strength of belief, or concerns about other models, or other factors that would be important. And, yes, science is very different from magic.

I'm not a physicists, so I have no right to answer your last question.

It's known that both Copenhagen and Everettian models have unexplainable weirdness - events that do not occur to us in the macro world and appear absolutely impossible. The Everettian model is attractive in how it is a clean and direct interpretation of the Schrodinger equation. Copenhagen requires a significant amount of modeling to avoid multiple worlds, but in doing so it introduces ideas that also appear to be totally impossible.

I wonder if Everett's model is less popular because of the difficulty in getting to testable solutions in an environment of multiple worlds. I've heard nobody say that.

 

The standard model has changed repeatedly over the years. It is what science is all about. The big bang itself is just a theory. It may reflect the current standard model but it certainly isn't settle science.

 

Hence, your answer concurs, completely with my suggestion-- which nevertheless, you'd devoted so much lineage to, supposedly, refuting. Now, look above , at the emboldened words in your quote-- written by you. That was exactly my point, all along, to which you made verbose and passionate counterargument, every time I repeated it. Can you explain, then, why that was?

For reference, from my first post, on the subject:

How do you see what I was saying, as intrinsically different from what is implied by your own admission, at top?

Yet, you had begun your non sequitur answer to that first post of mine, thusly:


WillReadmore said: ↑
There must be monumental justification for deciding to discard what has been tested every day for a century.


To which I'd pointed out:


DEFinning said: ↑
...

And yet, changing your phrasing to, for example,

We believe that nothing, not even information, can travel faster than c,

as I had suggested was the more accurate way to relate this idea, would not be a discarding of anything-- would it?



Nevertheless, you'd followed that with a repetion, of the same, non sequitur point:


WillReadmore said: ↑
...
But, that does NOT justify pretending that our most solid understanding of the physics of this universe may be offhandedly ignored, as if breaking our fundamental understanding is no more than an engineering problem that hasn't yet been completed.


Followed by my my third stating of the concept, after asking for you to show where you were getting your erroneous charge, that I was advocating "ignoring" or "discarding" anything (which you never supplied):

DEFinning said: ↑
And who, pray tell, was "pretending that our most solid understanding of the physics of this universe may be offhandedly IGNORED?"

If you are going to contend that it was me, would you please snip out the specific sentence(s) in which I do so?

The suggestion of my comments, applied to your fallacious implication, <made in your reply> would result only in the slight addition, of your saying, for example:
"...our most solid understanding, at present, of the physics of this universe..."

my point concerns only the way we CONCEIVE, and so SPEAK, of our understandings; not the way we apply them...

The purpose of, or advantage in adopting this change, I explained, was to avoid obscuring the lines of exactitude, in our certainty about different things. Through your own, obvious, rejection of my proposition, you help me demonstrate its value: based on my original objection to the certainty with which you'd stated things about the speed of light (represented as "c"), your current statement about offhandedly ignoring "our most solid understanding of the physics of this universe," can only be taken to mean that you are including your earlier statements, that nothing in the universe, including thought, can move faster than light speed, as being on an equal level of our certainty, as the most fundamental, best established principles in the physical sciences. This is clearly hogwash, and no knowledgeable scientist worth his salt, would agree with that. Nevertheless, I do not say, that because of the language that nearly all, lazily use, this is not only the impression they can give others, but also the fact which they, themselves, in practice, often forget.

In your resisting acknowledgement of our limits in knowledge, and therefore levels of certainty we can really have about different aspects of the "physics of this universe," you simply portray the image of someone who stubbornly adheres to a senseless approach, based only upon one's comfortable, if highly flawed, habit. Your, now second, reply, completely missing my point, and making an argument that is utterly divorced from what I am saying, is yet more evidence of that mindset, you are trying to defend. In doing so, it is in fact yourself, who is doing the "pretending."


This, you responded to by saying you could not discern the difference between the manner in which we speak of an idea (as in describing, or teaching it) and the way we apply it (as in using its concept, in some equation).

Jumping to the next exchange, you immediately returned to speaking about the "cosmic speed limit," as if it wasn't a theory, which could be, and was, credibly disputed by physicists but, instead, as one of our most "fundamental understandings" of science.


WillReadmore said: ↑
The cosmic speed limit doesn't change based on what the particle is. The speed limit is a property of the universe. And, it is not dependent on where you are in the universe, whether the universe is expanding, etc.

This is more of what I'm pointing to. We've grown to take a casual view of physics - and other sciences, too.


Au contraire-- it is a casual use of language, which you display. How is your statement, here, not as indictable as is Hawking's, by your own statement, quoted atop this post:

"it includes no indications of context or strength of belief."

To the contrary of acknowledging that this is the accepted theory, at present-- the "indications" of your "strength of belief," in the statements above, is that they are irrefutably proven fact, and a certainty:

--The cosmic speed limit doesn't change, based on what particle...
-- The speed limit is a property of the universe.
-- And it is not dependent on where you are in the universe
-- (or on) whether the universe is expanding, etc.

And we know this, beyond a doubt, because we have checked it, from all parts of the universe? And under different universal conditions (of expansion and "etc.")? Of course, we can say that all particles adhere to this limit, because we are aware of all particles, and have certified this, as well?

No, the theory, while it seems generally true, we have a far insufficient basis to know that it is absolutely true, which is the way you portray it, in your choice of words.

Because you have had such past difficulties with understanding such obvious discriminations, I will show you an example of how you could have indicated the appropriate "strength of belief:"

-- The cosmic speed limit, theoretically, doesn't change, regardless of the particle...
-- It is believed to be a property of the universe.
-- Assuming we're right about this, it would hold true in all parts of the universe...
-- and we predict that this property would be unaffected by any local or overall condition of the universe, such as whether or not it was expanding, and so on.

Question: isn't it predicted that things being swallowed into a black hole, move faster than light? Or is this unknown/only theoretical? And so, therefore we could not consider that unproven theory, in affecting the definiteness with which we express the extent to which the cosmic speed limit theory, applies to all places, and under all conditions?

 

Once again, you totally take what I said out of context and type paragraph after paragraph in your attempts to find fault.. So, I'm ignoring that for now.

As I pointed out, the cosmic speed limit does not require knowing the particles. It's not based on that.

There isn't knowledge of what happens inside the event horizon of a black hole. But, the mass of a black hole would prevent exit, due to needing to travel FTL.

 

Hence, there also isn't knowledge of our entire universe, and all possible conditions, in order for you to state, sans caveats, that this speed limit applies in all places, in all cases, and under all conditions, as a fact-- which is the way you'd expressed it. There are so many ways you could have acknowledged our less than thorough, informational basis for this theory, which you nonetheless acted as if, was comprehensive. Based simply on the fact that it is accepted by all physicists that there are particles (how many, none can say) which we have yet to discover, and so which we obviously have not been able to measure their speed, it is inaccurate to pretend that we can state anything about the speed, of all particles. Simple fix: "no known particles, exceed the cosmic speed limit..." etc.

So you are doing the same thing that we both agree, was Hawking's irresponsible and unscientific way of speaking-- or, in your less clear description, something that has "a level of indirection that raises serious problems." You did not exclude black holes, from your blanket statements-- if you do not wish to specify potential exceptions, the word "generally (or typically)," can be very helpful, in this regard-- you'd just acted as if they didn't exist, or as though we knew they conformed with your statements; same with all those particles we have yet to discover.

When can scientific fact, not be based on empirical evidence? Answer: when it is based on a theory. But then, it isn't properly, scientific "fact"-- even if that is how many express it (with problematic "levels of indirection").

I did no such thing, as take you out of context, in the slightest, meaningful way. Considering all the ground I'd needed to cover, I think I provided an excellent, and accurate, overview of the conversation, within a reasonable length (and I think my editing tools were effective in saving one time on longer quotes, while giving a good sense of the ideas, yet still providing those highlights, within their original context).

Once again you, are accusing me of something, without offering any evidence. If you had seen instances of my taking you out of context, how easy of a thing it should have been, for you to offer these, and debunk my presentation; yet you support your allegation with no quotes, demonstrating this supposed "totally" taking your quotes "out of context." Nor did you even explain a single, specific example. What would be the logical, scientific theory, based on those facts?

 

What made you think that there will ever be a time when all questions are answered?

The cosmic speed limit comes from relativity theory. We're essentially testing relativity theory through observation of cosmology, back to the cosmic microwave background radiation. There are known to be changes in expansion rate of our universe, but that doesn't defy relativity theory.

The speed limit is not dependent on particles that could be found. You can imagine any kind of particle you want.

I've never seen you cite a statement by Hawking. Maybe I missed you doing that at some point.

Yes, you indirect references without citation are NOT good enough as I've pointed out many times.

It's misleading to caveat all physics because of not knowing what's inside a black hole or not knowing what brought about our universe. There are some things we just have to know. I'm not going to repeat that for all discussion of physics.

A fact in experimental sciences (scientific method, natural science) is a well documented observation - like a temperature taken with a specific device at a specific location, ...

Everything in the natural sciences is available to be contested. There is NO proof like there is in math, because in math all possible dependencies are known, while in natural sciences they might not all be known. For example, Newton did know about light speed, so his physics doesn't handle that.

Theory is the very best understanding that natural science can provide. There is nothing stronger concerning how something works. Relativity is a theory. Evolution is a theory. And, you have to watch your 6, because this is a different use of the word than in public life or theoretical physics.

Again, the levels of indirection refers to me noticing you paraphrase Hawking without a cite. That's not good enough. If you want to whack Hawking, you have to cite what he said that you don't like.

Again in this post, you refer to me agreeing with something you said about Hawking, and DON'T DO THAT! As I keep telling you, I don't agree with you on something someone else said without an actual cite.

 

Duh-- the language you use, suggests that we already have answered all questions, in many areas! That has been my point. Your words do not express the idea, that "this is what we now believe, though there is more that we don't know, which may change that." Do you want more examples, on top of all of your statements, about which I've previously pointed this out? Why don't we stick with recent phrasings of yours, which I've already indicated as overstating our certainty?


A) My version, which acknowledges that "all questions are" not answered:

"No known particles, exceed the cosmic speed limit"


B) Your version that implies that the question of how fast can anything in the universe can move, has been answered:


"The speed limit is not dependent on particles that could be found. You can imagine any kind of particle you want."


That is from your current post. You have made essentially the same claim, at least several times.

 

Those two statements are not in conflict.

"His special theory of relativity gives a mathematical explanation for the cosmic speed cap: as objects with mass accelerate to higher speeds, they require more and more energy to keep them accelerating. To attain light speed, you need infinite energy – an impossibility. Light only gets a free pass as it has no mass, as …:

https://www.amnh.org/exhibitions/ei...ext=So why can't you,reach the speed of light.

I mentioned particles, because there is an idea from theoretical physics that there are tachyons. These particles could travel faster than the speed of light, but no slower - trapped on the OTHER side of the cosmic speed limit. There is no evidence supporting this idea.

This doesn't change relativity theory, the source of the cosmic speed limit.

There is another particle with no mass - gluons, also called gauge bosons. They have no mass, and thus they travel at light speed.


I probably should have ignored that.

 

I'm a proponent of multiverse also. For me it is the most logical explanation for the increasing velocity at the edges of the universe away from the center (wherever that is.) If we accept the concept of gravity then the edges should be slowing but instead something outside the universe seems to be pulling. It seems a little arrogant to think we have the only universe. We can be excused because we can't see anything beyond our universe. But perhaps we should accept that we see the effects of things beyond our universe.

 

Another proposed solution:

Physicist: There is no Dark Matter and the Universe is Twice as Old as We Thought

'When the James Webb Space Telescope was first launched, the scientific community knew that it was going to be a Very Big Deal. The instrument would allow us to peer further than ever across the depths of space (and backward in time) and do so across multiple bands of light. The JWST has delivered on all of those promises and more, sending many astronomers and physicists back to their chalkboards to reexamine previous theories and assumptions. One of the biggest examples of this phenomenon may have arrived this week. Dr. Rajendra Gupta, a theoretical physicist from the University of Ottowa made a remarkable announcement recently. He claimed that new data suggests that the universe is nearly twice as old as the 14 billion-year figure we've been given for a very long time. And if that's true, he further claims that there is no need for anything like dark matter to exist because the universe is behaving precisely as it should. That would really change the landscape of current astrophysics.'

Supports the Big Bang - only 27B years ago, rather than 14B

'Sound waves fossilized in the maps of galaxies across the Universe could be interpreted as signs of a Big Bang that took place 13 billion years earlier than current models suggest.'

'Gupta went on to state that if the universe is 26.7 billion years old as his team believes, "the Universe does not require dark matter to exist." Previous studies all suggested that the universe is expanding faster than it should be based on the amount of physical matter we are able to observe in space. That's why physicists had to dream up dark matter (and its corresponding partner, dark energy) to explain what was being observed. But the vastly larger universe now being posited would allow for the apparent motion of all of the heavenly bodies.'

https://hotair.com/jazz-shaw/2024/0...iverse-is-twice-as-old-as-we-thought-n3784900

 

I have a friend who is a PhD physicist. I asked him about dark matter when it first came up in the scientific literature. His response was that he was skeptical of the idea because we can't see or sense dark matter. He viewed it as a theory designed to try to explain some things we didn't yet understand. Perhaps he was right.

 

One can read descriptions in wiki of why physicists are sure there is dark matter..

You PhD friend had every reason to be skeptical when the idea first came out. That's what happens with a lot of what gets discovered. One has to wait a while for smart minds to figure out what the observations actually mean.

It's similar to turning on the Webb telescope and wondering what's being seen and whether it counters known physics.

 

I've always been skeptical of dark matter, an invisible substance that outweighs visible matter 6 to 1. It may be just a number plugged in to get the math right.

 

He hasn't changed his mind. He believes we don't understand what it is that people assign to dark matter and dark energy. These are theory, not settled science. Pretty hard to settle science that is not observable or observed. I'm not saying these physicists are right or wrong. I just explained that it isn't settled science.

 

It is a lot like all those equations that contain the infinity symbol. Science says nothing is infinite.

 

Dark matter is something that is observed and measured. It is not hypothetical. It doesn't interact with the electromagnetic spectrum, so it's one more thing that we can't see with our eyes. But, we can watch it interact through its gravity.

What is not known is exactly what it is. That's where the theory comes in.

At one time, we knew that electricity existed, but we didn't know what it is.

 

If you can't observe it, and you can't, then you give it a name and use it to make the equations work properly. There are possibly more mysteries than facts in cosmology. I think "dark" things point out that there is something about what we do observe that we don't understand. You said as much. The big bang theory is under attack also thanks to the new telescope. We don't appear to understand that either. Science is about demystifying mysteries and it has a lot more to demystify.

There is some debate about what electricity is also. Its effects are certainly understood and measured, but its nature is uncertain. It's OK. It is what science is all about. We understand more every day.

 

Well, as I pointed out it is observable - just not by electromagnetic radiation (such as light).

Yes, "dark" means there is something not understood. And, exactly what makes up dark matter is theoretical at this point.

But, that does NOT mean it doesn't exist - just like anything unknown about electricity doesn't challenge its existence.

 

It isn't observable by any means. That scientists support it points out that we don't have a full understanding of gravity, since dark matter is considered to affect gravity in some way. Perhaps gravity is only partly affected my mass. There may be more to it than that. These are just mysteries of the universe.