Do philosophy people have a reputation? — TiredThinker

From my perspective (an old mathematician) philosophy people looove to talk and write, sometimes going on for paragraph after paragraph elaborating upon a concept that I would have described in a couple of sentences. But I see that as my fault, being too concise, failing to expand and not enjoying writing as much as others do. The writing on this forum can be very impressive in both quality and content, but I fade away after reading a few lengthy paragraphs. :yawn:

Whatever mankind does to itself will ultimately be dwarfed by what nature does. Beyond looming climate change, which might be benign by comparison, the Yellowstone cauldron and similar eruptions, plus an asteroid or two can be truly catastrophic.

It's just that moving clocks seem to move slower. If you accelerate them they actually move slower. — Raymond

The clock hypothesis is the assumption that the rate at which a clock is affected by time dilation does not depend on its acceleration but only on its instantaneous velocity

Contrarily to velocity time dilation, in which both observers measure the other as aging slower (a reciprocal effect), gravitational time dilation is not reciprocal. This means that with gravitational time dilation both observers agree that the clock nearer the center of the gravitational field is slower in rate, and they agree on the ratio of the difference

(Wiki)

However, I am certain that time dilation (whatever it is) did not involve Absolute Time. — god must be atheist

Not sure there is any such thing. As we watch a spaceship fly by at half the speed of light times the linear 0< t<1, both the spaceship crew and you and I experience time as linear, however the passage of time on the spaceship as recorded here on Earth is curvilinear.

Time dilation during the early stages of the Big Bang makes the notion of an infinite past debatable. It would seem that an "infinite past" would be bounded nevertheless.

On the concept of the number of many worlds in quantum theory, David Wallace (2011) has this to say:

To be sure, by choosing a certain discretisation of (phase-)space and time, a discrete branching structure will emerge, but a finer or coarser choice would also give branching.
And there is no “finest” choice of branching structure: as we fine-grain our
decoherent history space, we will eventually reach a point where interference
between branches ceases to be negligible, but there is no precise point where
this occurs. As such, the question “how many branches are there?” does not,
ultimately, make sense.

Not an argument, just an observation somehow related to the OP.

*if* the information content of the universe is finite, *then* the number of possible universes is countable — hypericin

You are assuming another possible universe is simply an extension of the one we are in, adding features here and there. How could you possibly know what a different universe might be? It might be indescribable from our limited perspective. You seem to be simply shuffling around the features of our universe and applying them to other universes. Its physics, if it had one, might be incomprehensible. Its math could be different, in which case the word "possible" in the OP makes little sense.

It's clear I'm not seeing these many worlds from your perspective. And I'm not restricting myself to solutions of wave collapse in our universe.

I would ask, "Why is the causation 1/2^n power? — Philosophim

OK. At the present time we have a result of causation from an event having taken place 1/2 a year ago. At that time a previous event caused that result, the previous event having taken place 1/4 of a year prior to that event. Keep going back in time in this manner and you never reach an origin for this causation sequence, although the causation sequence started no further back in time than one year ago.

Silly nonsense.

If an infinite regress of prior causes leads to a contradiction, then there has to be a first cause. — Agent Smith

Suppose the infinite regress is a causation sequence that, going back toward an origin, is of the form 1/2^n. You never reach the origin, but the chain exists. Just babble :roll:

Most of these articles will not be worth the paper they are printed on, no matter how brilliant they are. They will remain still born — Tobias

Fortunately, it's the exploratory effort that gives them meaning. Publication and citing gives them reward.

If it is finite, we can encode it as a (very, very, *very* large) integer. Think of binary data as a universal medium of information. All binary data, no matter how large, is just a base 2 integer — hypericin

This type of comment comes up every so often. Alexandre used it some time back. Exactly how do you do this encoding? Is it arbitrary?

So then the set of all possible universes is representable as an infinite array of integers. — hypericin

Hence, you assert the "number" of possible universes is countable. That's a big "if".

The only way I can see the op succeeding is if the information content of the universe is finite, there are only a finite number of possible universes, and by some law universes cannot repeat in the multiverse — hypericin

Alexandre made that assumption also.

If there are other universes the principles of probability we have assembled may not be the same. We can say absolutely nothing about the nature of other universes. But they can make for good science fiction. :smile:

Something doesn't add up — Agent Smith

All of us who use Wikipedia should contribute some $ now and then. It will continue to exist but may have to start accepting ads.

That is exactly what we do in academia nowadays... we are not trained to be revolutionaries. Part of me resents it, but another part of me sees wisdom in this slow but meticulous grinding of our lens... — Tobias

Yep. I like the "little pepper-corn" analogy. I've mentioned before that the number of new research papers in math alone arriving at Cornell's ArXiv.org surpasses 250 per day.

What's fascinating about reality requiring an observer is that there must've been at least ONE from the very beginning of reality — Agent Smith

Right. Otherwise it could not exist now.

Some time back the president of the American Mathematical Society could do this juggling trick.

What is it about these big-shot intellects that they are attracted to this sort of thing? :chin:

Either the state of the universe can be represented by a real or it cannot. — hypericin

It would make more sense if you questioned whether the number of objects in the universe was finite or infinite, then countable or uncountable. What does it mean to say the "state of the universe"?

Sorry, makes no sense to me. If you're talking about dynamical systems and their states you must explain all the details.

In brane theory, a 3d brane, on which matter is constrained, is emerged in a 4d space. When the branes . . . — Raymond

It's intriguing to think these things "exist", an effort to comprehend the physical universe - or simply a devise to create working models.

Either the universe can be so represented, or it cannot, because the universe is too complex. But if the latter, then my argument is only strengthened. — hypericin

nullum sensum facit

Why are these pictures misleading? — Raymond

Implied by

You are completely right. It is wrong to think that ‘geometrization’ is something essential. It is only a kind of crutch (Eselsbrücke) for the finding of numerical laws. Whether one links ‘geometrical’ intuitions with a theory is a … private matter

Einstein, from a translation of a letter to Reichenbach in 1926.

Drop a brick on your foot. No force, huh? :lol:

But in GR space is curved inherently. — Raymond

Once one moves into 4-D, the "curvature" of space becomes an algebraic concept, not a geometric concept. And implications back to 3-D probably remain algebraic. Einstein called gravity a force. All those images of Earth sinking into a net and balloons expanding are misleading. IMHO. :cool:

You are missing that space for an accelerated guy is curved. That's the weird thing about space. — Raymond

In four dimensions, yes.

You are now the third person, who I have discussed cosmology with, who has stated, with serious conviction that they know the structure and origin of the Universe.
Each as convinced as the other that they are right and the current popular hypotheses are wrong. — universeness

:cool: :up:

I have a proof that time is real. I'll show it to you — Banno

That's unreal!!! :gasp:

Space expands, objects such as solar systems or galaxies do not expand as they are gravitationally bound. A common analogy is pen marks on the surface of a balloon being blown up — universeness

Thanks. It's nit-picking, but space itself has no substance and does not "stretch" as the balloon analogy suggests. The metric changes and objects not influenced by gravity move apart. This is one way of looking at the expansion of the universe. Spacetime is more complex. There's lots of material on curvature in mathematics, but I'm not sure about applications to pure space. Beyond my paygrade.

Isn't so called (velocity/gravitational) time dilation, a case of warping the 4th dimension (time); however, unlike space in which case a straight line becomes a curve, with time, a curve becomes a straight line. — Agent Smith

Curvature occurs in spacetime, rather than in 3-D space is my (pathetic) understanding.

so, expansion of space, is the notional 'clock' ticking. The current expansion rate is accelerating — universeness

Is it space itself that expands, or matter within space?

(A year of physics at GaTech in 1956 didn't prepare me for the modern world of physics)

Mathematicians can play with time, real or unreal:

Playing with Complex and Distorted Time

If there was any physical substance to time it would be a topic in fluid analysis. Perhaps it flows in the aether? :chin:

As the saying goes, just Shut up and calculate. Do what you can with what you have.

Rural America is rife with ignorance and superstition, dull-mindedness, racial tension, religious prejudice and a tendency to be cowed by celebrity mystique: the antithesis of Enlightenment values — ZzzoneiroCosm

Do you live there? You must to have witnessed this horror. :scream:

Infinite Compositions of Analytic Functions

If F is a functional operating on a function f, then F(f) makes sense, but F(F(f)) does not. Functionals map functions to real or complex numbers and not to other functions. Operators can take functions to functions.

Assume U = Time is unreal.

If U is true then there must be a proof (call it ϕ1) that U — Agent Smith

Why? Is time is unreal a mathematical theorem?

Since we experience the passage of time it seems quite real. But not physically so like a doughnut.

How would that make a difference? — Athena

I like the idea of driving an electric car. As a high school student in the early 1950s I would take the electric buses in Atlanta downtown frequently. But an accident involving electric vehicles is scary. All that electrical energy could fry you to a crisp. Gasoline is dangerous, too, but it's not "alive" like electricity.

But imagine all those cars, buses and trucks running out of power in dire conditions, and then efforts to charge them all to get started again. Whereas along comes a truck squirting a couple of gallons of gas into tanks as it slowly passes by.

However, technology will improve for E-vehicles.

From the Aaronson blog:

But Tegmark goes further. He doesn’t say that the universe is “isomorphic” to a mathematical structure; he says that it is that structure, that its physical and mathematical existence are the same thing

I'm with him up to an isomorphism. Beyond that is the absurd IMHO.

Both idealists and realists can agree with the Ontic-Structural Realism of Tegmark. For example, British idealism's doctrine of internal relations is in logical agreement with OSR, without jumping the shark to conclude that only unthinkable and unperceivable mathematical structure exists in a way that is divorced from the Lockean secondary qualities of perception — sime

Whatever. As I mentioned in another thread, a simple isomorphism between physical reality and mathematical structures provides a way of saying they are the "same" without being identical. But if this is truly what Tegmark had in mind he overdid his arguments - as do some posters on this forum. :cool:

Rather than insist that our intuitions are wrong and that the mathematics is right, we can instead insist that our intuitions are right by switching to an arguably more realistic axiomatization of geometry in which the paradox is dissolved or doesn't arise in the first place, such as computational geometry or intuitionism. — sime

Try the Taxi Cab metric.

Please die, thread. Poor thing, I should never have started you. This is wandering in the direction of threads having hundreds of posts devoted to the meanings of "2+2=4" :worry:

The instability, ambiguity and uncertainty that characterises mental imagery and perception complements the realities of mathematical undecidability and finitistic reasoning that intuitionistic geometry recognises and which classical geometry ignores, while Brouwer's theory of choice sequences parallels how one visualises or recognises "infinity" (i.e. as a finite random truncation of a vaguely sized process). — sime

Whatever this means, the paradox is not that big a deal. Aristotle may have been aware of the fact that arc length is not preserved in this kind of process.

3.333 The reason why a function cannot be its own argument is that the sign for a function already contains the prototype of its argument, and it cannot contain itself.

alcontali is taking the expression F(F(x)) as function composition, ie compute x1 = F(x) and then compute F(x1) , and x could be an integer and F(x) returns an integer. That is different from the question considered by Wittgentstein, which is could there be a function which takes the function itself (the mapping) as an argument? — Robert Durkacz

As a retired mathematician I read the OP and thought, This is utter rubbish. I have worked with infinite compositions of functions for years. But some degree of clarification followed. Thinking of a function as a collection of ordered pairs helps.

There is no god battering the eaarth with his wrath, it's simply a natural fact that if we impose an artificial technological order on nature, the natural order will get fucked up and natural chaos will replace it — Raymond

Imagine if all those vehicles stranded on I95 for 24 hours in snow and ice had been electric.

By your logic, when I walk a mile on a flat surface, I should say I walked more than a mile. — T Clark

Only if it pleases you to do so.

This is a mathematical can of worms, with definitions and counter-definitions. In the physical world certain phenomena may exhibit what we normally think of as randomness. What comes to mind is recording very slight changes of atmospheric pressure in some sort of controllable context.

Since there are algorithms predicting successive digits of the square root of two, from one perspective those digits - the sequence - would not be considered random. But for practical purposes the sequence could be considered random.