The blue hue is called Cherenkov radiation. It happens when a particle moves through a medium early fast, leading to light being released. It’s like a sonic boom but for light.
As for the green glow, maybe it’s due to uranium glass glowing green unused UV light.
When a photon (a light particle) enters a medium, it's speed drops somewhat. Lightspeed-the-universal-constant, however, is unchanged; so at that point it becomes possible for another particle in that medium to go faster than light.
When that happens, you get Cherenkov radiation.
"Really fast" indeed 😁 (i assume you know this, but I found it worthwhile to add a little clarification that it's not formula-1-really-fast)
Not really "faster than light", but faster than light in that medium. The phrase "faster than light" normally refers to moving faster than c, which particles with rest mass can't really do according to our current models.
Nothing travels faster than c, or the speed of light within a vacuum.
The speed of light within a medium (like water) is not c. It is less.
When a particle is traveling at c and slams into a medium like water with enough force it will continue traveling faster than light normally would in that medium, and give off that radiation as it does.
But it is not traveling faster than light as you emphasized. It is traveling at nearly c and getting slowed down. It is often referred to a "light based sonic boom" though because that makes sense. But only when you consider the transition from vacuum to a medium or medium to medium.
Protip: anytime someone points out a thing is traveling faster than light they're wrong because really: nothing does ever. It isn't physically possible and the smartest minds on the planet have tried to reason how it might be for nearly a century now, with no progress at all. There are workarounds but they don't involve "travel" in the real sense, more like displacement.
They used to have radioactive decoder rings and other toys that glowed green in the dark. They also used to paint all sorts of things with radioactive paint to glow in the dark like instrument panels.
In 2023, yeah, but remember that it isn't in 2023 that the association was made.
Tritium watches used to be a much bigger deal some decades back, as you could actually use the thing in the dark. Subsequent to that, battery-powered digital watches with a light became common, and then a lot of people just moved to using a cell phone to know the time.
As the linked WP article details, uranium glass also used to be more-common prior to the government locking up a lot of supplies of uranium. I've only seen uranium glass in person in museums, and in general, plastic has displaced a lot of glassware today.
Tritium is also still very popular for firearm night sights. And I'm sure some radium painted one used to be as well. The night sights on my SKS may have been radium paint or just regular phosporescent paint, or may have had tritium vials that fell off.
For a while there was a full set of uranium glassware in my local antique mall for sale but I think someone bought it.
I'm having a feeling it's a combination of other stuff mentioned here like radium, which was then put on The Simpsons and then that's what everyone got the idea from. They made nuclear waste a green liquid and that's the cultural zeitgeist there, probably.
So, this is a basic misunderstanding of gravity and acceleration. The measure of Gs is the exact measure of how fast the acceleration is.
This is just like asking if it would be comfortable to survive 100 C if the temperature was cold enough.
There is no difference between acceleration and gravity. If locked into an elevator, you wouldn’t be able to tell with certainty if the elevator started going up, or someone had just turned the gravity of the planet up to make you heavier somehow. If the elevator suddenly dropped in freefall, you would not be able to tell if it was the elevator moving down, or someone had simply turned gravity off somehow. This is part of Einstein’s Special Relativity.
It's a bit more easily understood if you look at a space-time diagram, but essentially it kind of boils down to the speed of an object through space and the speed of an object through time are related and they must add up to 1. So if you're traveling at 50% the speed of light through space, then you're traveling at 50% the speed through time compared to an object at rest. So if you're traveling at 100% the speed of light through space, you're traveling at 0% through time, or not at all.
I’ve read about this but it kind of loses me since it’s such an abstract model of what’s going on. It treats each dimension as equal but like, time certainly seems distinct from the 3 spatial dimensions too.
I know it’s legit and a proper way of understanding it though just nitpicking since it leaves me with a sense of fuzziness like, maybe a gross oversimplification?
Granted I know it’s only meant to explain what’s happening in a predictable way not actually address the nature of these values which I guess is what I naturally lead into wondering about
I found this channel (Science Asylum) really helpful in explaining things very simply. He uses space-time diagrams in this video to explain how gravity is an emergent property of time and how the two are linked together.
I assumed that once we decided what a second was, that’s what we’re going off of for that 13 billion year assessment.
I guess that’s mostly correct from what I can find online.
From the point of the big bang or creation or whatever, time has been progressing second by second for 13.7 billion years.
With the consistency of time measurement scientists use, it seems like that’s why they use conventional standards of time to measure how long the universe has been around.
Time moving slower inside a black hole's gravitational field would have the opposite effect from what you're thinking. Like in the movie Interstellar, when they go down to the water planet they say "one hour on this planet is equivalent to 7 years on Earth".
So any civilization within a black hole's gravity well would actually be at a huge disadvantage and have considerably less time to prepare.
I use extra virgin olive oil for marinades and salad dressing (and an olive oil spread instead of butter or margarine) and rapeseed oil (usually just labelled as vegetable oil here in the UK) for frying. The latter has a high smoke point, is lower in saturated fat compared to sunflower oil (also higher in monounsaturated and lower in polyunsaturated fats, a bit like olive oil although that has even better proportions of the two) and has better levels of Omega 3.
vegetable fats can change during the cooking process, breaking down into harmful chemicals, including aldehydes.
…
The stability of the oil is important too: some oils, like sunflower oil, are more likely to oxidise when heated – or combine with oxygen in the air – producing harmful compounds in greater quantities. A 2012 study by researchers at Spain’s University of the Basque Country reported that aldehydes can react with our hormones and enzymes.
With the issues with sunflower oil after the invasion of Ukraine the UK’s Food Standards Agency drew up a report about the substitution of other oils, which has plenty of data.
A switch away from sunflower oil should reduce levels of heart disease, following this paper:
Zatonski et al. [25] examined trends of mortality due to coronary heart disease (CHD) and fat consumption in eleven Eastern and Central European countries from 1990 until 2002. They observed that, in countries where sunflower oil remained the primary oil (such as Russia, Ukraine, Romania, and Bulgaria), the rate of CHD remained stable from 1990 onward. Meanwhile, in countries such as Poland, Czech Republic, Estonia, Latvia and Lithuania, which started to use rapeseed oil, a strong decline in CHD mortality was observed. This finding is confirmed in our study. Although both oils are rich in PUFAs, rapeseed oil contains more α-linoleic acid (ALA, C18:3), an omega-3 fatty acid with atheroprotective properties. Moreover, ALA is partly converted to eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), which may protect against CHD and cerebrovascular diseases [26, 27].
Redshift depends on the observer, so photons do not “experience” redshift until they are detected in an ordinary reference frame.
Furthermore, I’m not sure there is a good way to define what photons “experience” at all. Photons simply move through space until they interact with matter, and matter is never in the same reference frame as light.
Yeah I figure “experience” is sort of ambiguous and pop science-y, but it’s how I’ve usually had it explained.
That redshift depends on the observer is obvious now that you point it out and profound too since yeah, I suppose they’re not developing across space in the way I imagined.
This makes me wonder about a potential universe with nothing except photons/radiation in it. They’d just.. never change? Even though they could do things like affect spacetime they pass through or interfere with eachother?
The blue glow, Cherenkov radiation, is something that happens underwater, though. It's not really a drop-in replacement for, say, a puddle of radioactive waste.
I think that the problem is more that artists just want a way to indicate that something is radioactive, but we can't see radioactivity, so they had to seize on some sort of convention that deviated from the real world. It doesn't really need to reflect reality to work, just as long as the convention holds. And the practice of doing that in art isn't that new, either -- think of the halo, which serves a similar purpose:
A halo (from Ancient Greek ἅλως (hálōs) 'threshing floor, disk'; also called a nimbus, aureole, glory, or gloriole) is a crown of light rays, circle or disk of light that surrounds a person in art. It has been used in the iconography of many religions to indicate holy or sacred figures, and has at various periods also been used in images of rulers and heroes. In the religious art of Ancient Greece, Ancient Rome, Christianity, Hinduism, and Buddhism among other religions, sacred persons may be depicted with a halo in the form of a circular glow, or flames in Asian art, around the head or around the whole body—this last one is often called a mandorla. Halos may be shown as almost any colour or combination of colours, but are most often depicted as golden, yellow or white when representing light or red when representing flames.
Yes it is possible because it has happened. I'm not an expert, but I believe survival rates are connected more to duration than G force. If the body becomes unable to circulate blood and regulate itself for a long enough period of time, it dies.
That's exactly what happens. The human body cannot withstand more than 2-3 G for a prolonged period. Above that, the heart just can't pump blood and you die if you stay there too long. For instance, Stapp, the world record holder only withstood 46.2 Gs for a brief instant. Normally your blood weighs about 8-10% of your total body weight, so for the instant he was at 46.2 G, he weighed about 7700 lbs and his blood weighed between 616 lbs and 770 lbs.
That article is specifically about soybean oil, but sunflower oil also has a high linoleic acid content.
I think it really depends on your total linoleic acid intake. If you’re using a variety of cooking oils, and/or different cooking methods (e.g. steaming) then it probably doesn’t matter much.
Where I think it matters is when someone is taking in a diet of mostly prepared, highly processed foods that have things like soybean oil added.
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