Time may be an artificial construct, but it feels awfully authentic

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Time may be an artificial construct, but it feels awfully authentic

3 July 2025

Managing time when time doesn’t exist, from the Multiverse Employee Handbook, a science comedy podcast, produced by Robb Corrigan:

The real productivity crisis emerged when physicists tried merging Einstein’s relativity with quantum mechanics. They discovered something that would terrify any time management consultant: the Wheeler-DeWitt equation — quantum gravity’s fundamental mathematics — contains absolutely no time variable.

So maybe time doesn’t exist in the realm of physics, but who cares about physics when you’re running late for that train you must be on. Or when the hours and minutes are dissolving ahead of a critical deadline. Or anything else for that matter. And if time in fact does not exist, that’s not a problem either, the universe, and us along with it, carry on as usual.

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humour, physics, podcasts, science

UFOs, flying saucers, at Area 51, nothing but a military cover up?

12 June 2025

This sounds like the news that no one wanted you to hear:

The congressionally ordered probe took investigators back to the 1980s, when an Air Force colonel visited a bar near Area 51, a top-secret site in the Nevada desert. He gave the owner photos of what might be flying saucers. The photos went up on the walls, and into the local lore went the idea that the U.S. military was secretly testing recovered alien technology. But the colonel was on a mission — of disinformation. The photos were doctored, the now-retired officer confessed to the Pentagon investigators in 2023. The whole exercise was a ruse to protect what was really going on at Area 51: The Air Force was using the site to develop top-secret stealth fighters, viewed as a critical edge against the Soviet Union.

Hands up those who believe any of that, hey?

Otherwise, if someone could explain how extraterrestrials can travel vast distances through the galaxy to reach Earth, in vessels the size of a bus, apparently capable of travelling at the speed of light (or supposedly faster) without saying “oh, but they can bend the laws of physics”, I’m all ears. No warp powered motherships capable of cloaked flight either, please.

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physics, science

Milky Way might not collide with Andromeda, Milkomeda might not form

4 June 2025

Some recently revised calculations, based on some more recent data, have shown our galaxy, the Milky Way, may not collide, or if you prefer merge, with Andromeda, a large galaxy presently about two and a half million light years away.

Astronomers have long believed a merger/collision to be inevitable. Although heading towards to each other — at an eye watering speed of about one-hundred kilometres per second — there’s close to a fifty-fifty chance both galaxies will simply sail passed each other.

Milkomeda, the name given to the would-be merged entity, and something I’ve written a bit about in the past, may never come to pass after all. But then again it might, no one can be one-hundred percent sure. Uncertainty is the only certainty.

If you’re stilling gunning for the formation of Milkomeda though, here’s an animation of the what the collision might look like, from the perspective of a far distant observer. Events play out over ten billion years, but are compressed to a minute, meaning things won’t be quite as violent as they look.

Even if Earth were still around at this point — which seems unlikely in five billion years time — the merger/collision of the two galaxies would probably make little difference to anyone still here. Aside from an upheaval in the way the night sky looks, that is.

Despite appearances, galaxies are mainly made up of empty space, meaning the chances of a star from Andromeda barging into the solar system would be pretty remote.

Does the universe reside within a black hole?

17 March 2025

Good morning, welcome to the new week, and mind-blown Monday. Today we’re discussing life, the universe, the rotation of galaxies, black holes, and everything.

Data collected by the James Webb Space Telescope (JWST) has concluded about two-thirds of galaxies in the universe rotate in one direction, while the remaining third rotate the opposite way. In a supposedly normal course of events, the balance would be more even. Apparently.

But there is any such thing as normal in the cosmos? You know what they say. Truth is stranger than fiction. The universe is not only stranger than we can imagine, it is stranger than we can imagine. Two-thirds of galaxies might spin in one direction, because, you know, just because.

But there’s no just because in this universe. The imbalance in the rotational direction of the galaxies suggests to some astronomers that the universe was born inside a black hole. Since the black hole hosting our universe rotates in one direction, it follows that the majority of galaxies will spin in the same direction. Nikodem Poplawski, a theoretical physicist at the University of New Haven, describes this as the “simplest explanation” of the phenomenon:

“I think that the simplest explanation of the rotating universe is the universe was born in a rotating black hole. Spacetime torsion provides the most natural mechanism that avoids a singularity in a black hole and instead creates a new, closed universe,” Poplawski continued. “A preferred axis in our universe, inherited by the axis of rotation of its parent black hole, might have influenced the rotation dynamics of galaxies, creating the observed clockwise-counterclockwise asymmetry.”

I wonder how far up and down the “levels” of universes residing inside black holes goes then? If our universe is indeed located within a black hole, it follows that other universes must reside within the plentiful black holes that populate our universe. And inside those universes will be yet more black holes, that will be home to further universes. And so on.

But where does our black hole universe sit in such a hierarchy? Near the top? In the middle somewhere. Or near the bottom? If such a thing exists, as there may be no limit to how how far down the progression can go. The same applies going up the other way of course, in theory.

It’s mind blowing stuff for sure. If, that is, you accept this two-thirds versus one-thirds split of galaxy rotation represents a significant imbalance in the first place. There might still be room for just because here. After all, weird things just happen in this wondrous universe of ours.

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astronomy, physics, science

Gravastars and black holes, a weird cosmic double act

2 January 2025

The concept of gravastars (or gravitational vacuum stars) is a fascinating alternative to the idea of black holes, although if their presence were ever proved, they would not rule out the existence of black holes. Proposed by Pawel O. Mazur and Emil Mottola some twenty years ago, these objects are consistent with Albert Einstein’s general theory of relativity.

Gravastars, like black holes, form in the aftermath of some supernova explosions. They are relatively small, their size might be similar to London, capital of the United Kingdom.

In terms of appearance they are black, and a little like balloons, having an extremely thin shell, consisting of matter scientists do not yet understand. Their interior is filled with a vacuum, or dark energy, bustling to break out, but unable to do so. Gravastars sound like an incredible phenomena, but in a universe some think is devoid of dark energy, I wonder if they could actually be present.

Time, not dark energy, may be causing the universe to expand

27 December 2024

Dark energy does not exist, and the universe, while continuing to expand, is not doing so in a uniform fashion. In other words, the cosmos may look more like a potato, rather than a sphere. This according to recent research by astronomers and scientists at the University of Canterbury (UC), based in Christchurch, New Zealand.

As if that’s not startling enough, things become truly mind boggling when we look at the nature of time in a universe that may be devoid of dark energy. Time, you see, is moving at different speeds, depending on the location. Within our galaxy, the Milky Way, a clock ticks more slowly than one that might be situated elsewhere in an empty region of the universe, say the mid-point between our galaxy and the Andromeda galaxy, which is two and a half million light years distant.

The model suggests that a clock in the Milky Way would be about 35 percent slower than the same one at an average position in large cosmic voids, meaning billions more years would have passed in voids. This would in turn allow more expansion of space, making it seem like the expansion is getting faster when such vast empty voids grow to dominate the universe.

Because there is more gravity inside a galaxy than outside, clocks will be slower. This is a concept called gravitational time dilation, which Albert Einstein predicted when he published the theories of special relativity and general relativity, early in the twentieth century. Differences in clock speeds may not be surprising then, but the UC research illustrates just how stark these variations might be.

Shoot for the stars: Tim Teege wants to run a marathon on the Moon

20 December 2024

Hamburg, Germany, based web developer and long distance triathlete, Tim Teege is super keen to run a marathon the Moon. So much so, he wants you to ask any space agency worker type acquaintances you may have, to help him achieve his goal. Ask, and you shall receive, and the like.

Not to put a dampener on Teege’s aspirations, I wonder if he’s read Rhett Allain’s Wired article on the subject:

You can’t go out and jog around the Sea of Tranquility—you’d just start bouncing and floating.

But, as they say, where there’s a will, maybe there’s a way. The laws of physics notwithstanding. Yet here, at the quarter way point of the twenty-first century, the act of somehow being able to run on the Moon, should really be Teege’s only significant challenge.

Getting to the Moon — in this post 2001: A Space Odyssey world — should be as easy as boarding what ought to be regular commercial flights to Earth’s satellite.

The journey might cost a pretty penny, but that’s what crowdfunding is for. Instead, however, in what’s almost 2025, about all we have in terms of reaching the Moon, is NASA’s troubled Artemis program, which seems like a re-run of Apollo, yet appears not to be going anywhere fast.

With 2025 essentially only days away now, I shouldn’t be so indifferent. Big shoot for the stars ambitions and goals are what we need right now. Especially for this particular new year.

Vacuum decay, one more existential threat to lose sleep over

22 August 2024

Tooth decay. Entropy. Heat death of the universe. These are things to worry about, and we’ve known about them for a long time. But recently scientists have identified something else to lose sleep over: vacuum decay:

Vacuum decay, a process that could end the universe as we know it, may happen 10,000 times sooner than expected. Fortunately, it still won’t happen for a very, very long time.

There’s a lot of theoretical physics (I think) involved, which is way over my head, so there’s not more I can say about vacuum decay. The good news however: vacuum decay will not bring about the end of the universe anytime soon.

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The physics of running and keeping fit on the Moon

8 July 2024

Rhett Allain, writing for Wired, looks at the physics of this important question.

If humanity is ever to establish bases on the Moon, ways of keeping occupants fit in the low lunar gravity need to be worked out. A wall of death sort of gizmo, that’s a little like a stationary hamster-wheel, but turned on its side, that emulates Earth-like levels of gravity, may be a solution. But there might be more effective alternatives.

But check out the article’s artist impression of a suited up astronaut “jogging” on the surface of the Moon. Straight up running in this way is a fanciful keep fit option unfortunately, as simple as the idea may at first seem. It’s too bad though, because what a sight it would be to behold: Earth floating in the lunar sky, as you ran.

I doubt Earth would be quite as big as depicted in Nzoka John’s image, but it still be quite the spectacle. And on the subject of what Earth might look like from the surface of the Moon, a gallery of images by American illustrator and writer Ron Miller, depicting how other planets in the solar system would appear from Earth, if they were as close as the Moon.

Did the universe exist before the Big Bang? Maybe…

27 June 2024

What happened, or was there, before the Big Bang that is said to have brought the universe into being? Was there nothing, to which something came? It is the question of the ages.

In his recent documentary series, Universe, British physicist Brian Cox posits that the universe existed before the Big Bang. How long this pre Big Bang entity had been there, or its origins, remain unknown however. How fascinating these before-the-beginning sort of questions are.

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astronomy, philosophy, physics, science

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