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Squash the Berries!

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Just watched, best future of the universe clip I have seen, thanks for the post

The big crunch collapsing universe resulting in another big bang where life could exist offers some people hope.

Multiple universes, also provides some people with hope.

At this stage I'm sticking with the ever expanding universe resulting in dark nothingness theory as I have for the last 35 years.

 

Hacky McAxe

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Just watched, best future of the universe clip I have seen, thanks for the post

The big crunch collapsing universe resulting in another big bang where life could exist offers some people hope.

Multiple universes, also provides some people with hope.

At this stage I'm sticking with the ever expanding universe resulting in dark nothingness theory as I have for the last 35 years.

Agreed. There are very few physicists who support the big crunch theory now days. Based on the accelerated expansion and thermodynamics, there's just no logical reason to think that the Universe will begin retracting unless there is some rubber band matter that we haven't found yet.

More likely the Universe will keep spreading through dark energy expansion and fade through entropy until there's no energy or heat left in the Universe and nothing can exist any more.

There's an interesting thought experiment to explain part of the heat death of the Universe. It basically states that near the end of the Universe the entropy will be so great and we'll be so close to absolute zero that if any humans existing as brains floating in space, a single thought would produce so much heat that it would feel hotter than the sun in comparison to the Universe. Of course due to thermodynamics that single thought would destroy the brain as the last energy dissipates.
 

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I have always found Entropy to be a stange topic that's so simple yet so many physicists make it as confusing as possible while explaining it. I think this is the best and most simple explanation I have seen.

 

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Ceres is a dwarf planet and the largest known object in the asteroid belt between Mars and Jupiter.

And now we know it may be an ocean world with intriguing geologic activity taking place on and just below its surface, according to new research.

While this global ocean beneath the planet's surface likely froze over time, remnants of it may still be present beneath a large impact crater on Ceres.

The presence of salts may have preserved the liquid as a brine, despite cold temperatures.

The suite of seven studies were published in the journals Nature Astronomy, Nature Geoscience and Nature Communications.
 

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Mars is pockmarked with absolutely massive lava tubes, with ceilings as high as the Empire State Building, new research shows. And the moon hosts even more gargantuan tubes, with heights that dwarf Dubai's Burj Khalifa, the world's tallest building, and "skylights" as big as football fields.

These yawning, subterranean caverns, which are shielded from punishing solar radiation, could be used as sites for future human bases, scientists argue.

A lava tube is a tunnel under a world's surface, formed by an intense flow of molten rock during a volcanic explosion. On Earth, they're most easily spotted when they collapse, forming long furrows in the dirt. Partial collapses sometimes form chains of "skylights" that reveal hidden lava tubes that are mostly intact. Researchers have speculated that lava tubes might exist on Mars and the moon since the 1960s, but in recent years Martian and lunar orbiters have beamed home images showing how common these formations likely are, both on the Red Planet and on our moon. Now, researchers argue in a new paper published July 20 in the journal Earth-Science Reviews, it's time to explore them in earnest.

Here's why: These lava tubes are truly enormous, and might offer safer habitats than the lunar or Martian surfaces.
 

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I found this interesting.

www.bbc.com/earth/story/20160129-the-shrimp-that-has-turned-bubbles-into-a-lethal-weapon?fbclid=IwAR0COh9I-gPh7g9BCHd66ODBtZzvkbUWuLNIhz1aUutIetPHjOUTenqXEkw

A snapping shrimp can click its claws together and knock out its prey - without ever touching it


By Alex Riley
29 January 2016
Beneath the waves, there is a sound that is so familiar to mariners that they could easily misinterpret it as the sound of the ocean itself. It is a constant clicking that permeates the shallow waters of the tropics, day and night. Some liken it to the crackling of burning tinder. Others say it sounds like the snap, crackle, and pop of milk on cereal.

The source of the sound is actually a tiny shrimp equipped with an unusually large claw. When that claw snaps shut, it helps generate an intense burst of sound that can stun the crustacean's prey – snails, other crustaceans, and small fish.

Unsurprisingly, the small hunters have been dubbed snapping shrimps – although they are sometimes given the more evocative name "pistol shrimps".

But their claw is not just a stun gun. It is also their voice box. By snapping, they are able to communicate with their innumerable neighbours, each tucked away in its own den in the soft sand.

A prawn goby and Randall's pistol shrimp (Credit: Constantinos Petrinos/naturepl.com)
A yellownose prawn goby (Stonogobiops xanthorhinica) with Randall's pistol shrimp (Alpheus randalli) (Credit: Constantinos Petrinos/naturepl.com)
Snapping shrimps form large colonies that carpet the seabed. Some species share their burrows with goby fish in a mutually beneficial relationship: the shrimp offers the fish a place to live, the fish gives the shrimp protection from predators. There are over 1000 species in total, their ubiquity embellishing the underwater landscape with a rich, fertile soundscape.

The sound of the snapping shrimp is familiar to many who work in and on the sea

In fact, their communal chatter is so pervasive that it creates a white noise that fills the marine strata, from sand to water's surface – much to the annoyance of researchers trying to study the nuances of underwater acoustics in the tropics. The small crustaceans – they rarely exceed the size of your big toe – create irremovable interference that makes other sounds difficult to detect.

It is so difficult to hear anything above this crustacean cacophony that the sound might even have played a part in World War Two.

Between 1944 and 1945, the US Navy deliberately used snapping shrimp colonies as an "acoustic screen" to hide from the underwater hydrophones in Japan's harbours, allowing their submarines to enter undetected. The shrimp might even have had their own part in early atom bomb tests on Bikini Atoll.

In short, the sound of the snapping shrimp is familiar to many who work in and on the sea, even if they do not know it. They have been known to science since the late 18th Century.

But for most of that time, they were misinterpreted. Biologists believed that the sound they produced was merely a product of claw closure, one surface hitting another like slamming a door or clicking your fingers.

However, one physicist had other ideas.

Who would have thought of weaponised bubbles? (Credit: Image Source/Alamy Stock Photo)
Who would have thought of weaponised bubbles? (Credit: Image Source/Alamy Stock Photo)
In 1999, Detlef Lohse from the University of Twente in the Netherlands was looking at a printout of a sound track.

It was very clear that the sound is in fact originating from this collapsing bubble

The peaks and troughs of amplitude over time looked very familiar to him. He had seen a similar pattern from his work into cavitation – the phenomenon of bubbles collapsing with extreme force due to a sudden change in pressure, producing a bang.

The recording was taken in an aquarium in Munich that contained Alpheus heterochaelis, the bigclaw snapping shrimp. To Lohse, it all made sense: a cavitation bubble, not the claw itself, created the snapping shrimp's snap.

"I heard these zoologists say that sometimes a bubble is seen," he says. "So I combined that information, and for me it was very clear that the sound is in fact originating from this collapsing bubble."

To prove his idea, Lohse created watertight theoretical models and equations, accurately demonstrating that a cavitation bubble was the only explanation for such a sound.

The shrimp had to be slightly annoyed

"But zoologists are not convinced by mathematical models," he says. "They wouldn't believe me." Lohse needed to perform some experiments with real shrimp to persuade them.

Using a high-speed camera (able to take 40,500 frames per second), a set of underwater microphones, and a paintbrush, Lohse's colleague, Michel Versluis, was able to deliver the goods.

Wait… a paintbrush?

Stimpson's snapping shrimp (Synalpheus stimpsoni) (Credit: CB Images/Alamy Stock Photo)
A pair of Stimpson's snapping shrimp (Synalpheus stimpsoni) (Credit: CB Images/Alamy Stock Photo)
To induce a snap, the shrimp had to be slightly annoyed, through tickling – and a paintbrush proved to be the perfect tickling stick. Only then could the data collection start.

As revealed by the high-speed videos, when the snapping shrimp's claw closes, one pincer has a protuberance that fits snugly within a hole on the other, like the internal workings of a tiny garlic crusher.

With a bang, the bubble explodes into a shower of tiny bubbles

While the claw is open, the shrimp contracts opposing muscles to ratchet up the tension – then it suddenly releases this tension so that the pincers tear through the water at close to 100km/h and the claw violently snaps shut.

But, at this point – silence. Lohse and Versluis picked up barely a murmur as the two pincers clacked together. The familiar loud "snap" actually came a fraction of a thousandth of a second later; a small but significant delay.

As the plunger on one pincer is forced into the socket on the other, a fast jet of water is ejected. "And high velocity means low pressure," says Lohse. Consequently, a zone of intense low pressure forms around the shrimp's claw.

Any small air bubbles in the vicinity – known as nuclei – are inflated by this change in pressure and follow the flow of water.

A shrimp goby with its attendant shrimp (Credit: Chris Gug/Alamy Stock Photo)
A shrimp goby with its attendant shrimp (Credit: Chris Gug/Alamy Stock Photo)
But when the bubbles move far enough away from the claw, they encounter a huge disparity in pressure between the water outside and the air inside them. The bubbles collapse under the strain.

It can stun small prey, and can even dismember and kill small invertebrates and fish

"This is happening really fast," says Anna von der Heydt who worked on the theoretical equations of the shrimp's cavitation bubbles. "The bubble growth and collapse happens in less than one millisecond [a thousandth of a second]."

With a bang, the bubble explodes into a shower of tiny bubbles, reverting back into the same infinitesimal nuclei that started it all.

The shockwave produced from bubble collapse is not only very loud, it is also extremely powerful. It can stun small prey, and can even dismember and kill small invertebrates and fish. Snapping shrimp have weaponised bubbles.

A pair of snapping shrimp (Alpheus sp.) (Credit: WaterFrame/Alamy Stock Photo)
A pair of snapping shrimp (Alpheus sp.) (Credit: WaterFrame/Alamy Stock Photo)
Like an underwater firework, the exploding bubble generates light as well as sound. By placing the shrimps in complete darkness and using a highly sensitive photodetector – and, of course, a paintbrush – Versluis could show that each bubble collapse coincides with the production of 50,000 photons.

I will never get rid of the name 'the shrimp guy'

In everyday language: it was dim. It was imperceptible to the human (and shrimp?) eye. But it was extremely hot, reaching temperatures that matched the surface of the sun, albeit very briefly and in a very small place.

This phenomenon needed a name: something similar to "sonoluminescence", the process of light emission from bubble cavitation. "We came up with the name 'shrimpoluminescence'," says Lohse. "We invented this name over a beer."

Today, Lohse and Versluis still work together at Twente University, studying the physics of fluids and cavitation. Their offices are next door. The four shrimp that they used in their experiments, though, have long since died.

"It's been 16 years," says Lohse, "but I will never get rid of the name 'the shrimp guy'."
 

Hacky McAxe

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I found this interesting.

www.bbc.com/earth/story/20160129-the-shrimp-that-has-turned-bubbles-into-a-lethal-weapon?fbclid=IwAR0COh9I-gPh7g9BCHd66ODBtZzvkbUWuLNIhz1aUutIetPHjOUTenqXEkw

A snapping shrimp can click its claws together and knock out its prey - without ever touching it


By Alex Riley
29 January 2016
Beneath the waves, there is a sound that is so familiar to mariners that they could easily misinterpret it as the sound of the ocean itself. It is a constant clicking that permeates the shallow waters of the tropics, day and night. Some liken it to the crackling of burning tinder. Others say it sounds like the snap, crackle, and pop of milk on cereal.

The source of the sound is actually a tiny shrimp equipped with an unusually large claw. When that claw snaps shut, it helps generate an intense burst of sound that can stun the crustacean's prey – snails, other crustaceans, and small fish.

Unsurprisingly, the small hunters have been dubbed snapping shrimps – although they are sometimes given the more evocative name "pistol shrimps".

But their claw is not just a stun gun. It is also their voice box. By snapping, they are able to communicate with their innumerable neighbours, each tucked away in its own den in the soft sand.

A prawn goby and Randall's pistol shrimp (Credit: Constantinos Petrinos/naturepl.com)
A yellownose prawn goby (Stonogobiops xanthorhinica) with Randall's pistol shrimp (Alpheus randalli) (Credit: Constantinos Petrinos/naturepl.com)
Snapping shrimps form large colonies that carpet the seabed. Some species share their burrows with goby fish in a mutually beneficial relationship: the shrimp offers the fish a place to live, the fish gives the shrimp protection from predators. There are over 1000 species in total, their ubiquity embellishing the underwater landscape with a rich, fertile soundscape.

The sound of the snapping shrimp is familiar to many who work in and on the sea

In fact, their communal chatter is so pervasive that it creates a white noise that fills the marine strata, from sand to water's surface – much to the annoyance of researchers trying to study the nuances of underwater acoustics in the tropics. The small crustaceans – they rarely exceed the size of your big toe – create irremovable interference that makes other sounds difficult to detect.

It is so difficult to hear anything above this crustacean cacophony that the sound might even have played a part in World War Two.

Between 1944 and 1945, the US Navy deliberately used snapping shrimp colonies as an "acoustic screen" to hide from the underwater hydrophones in Japan's harbours, allowing their submarines to enter undetected. The shrimp might even have had their own part in early atom bomb tests on Bikini Atoll.

In short, the sound of the snapping shrimp is familiar to many who work in and on the sea, even if they do not know it. They have been known to science since the late 18th Century.

But for most of that time, they were misinterpreted. Biologists believed that the sound they produced was merely a product of claw closure, one surface hitting another like slamming a door or clicking your fingers.

However, one physicist had other ideas.

Who would have thought of weaponised bubbles? (Credit: Image Source/Alamy Stock Photo)
Who would have thought of weaponised bubbles? (Credit: Image Source/Alamy Stock Photo)
In 1999, Detlef Lohse from the University of Twente in the Netherlands was looking at a printout of a sound track.

It was very clear that the sound is in fact originating from this collapsing bubble

The peaks and troughs of amplitude over time looked very familiar to him. He had seen a similar pattern from his work into cavitation – the phenomenon of bubbles collapsing with extreme force due to a sudden change in pressure, producing a bang.

The recording was taken in an aquarium in Munich that contained Alpheus heterochaelis, the bigclaw snapping shrimp. To Lohse, it all made sense: a cavitation bubble, not the claw itself, created the snapping shrimp's snap.

"I heard these zoologists say that sometimes a bubble is seen," he says. "So I combined that information, and for me it was very clear that the sound is in fact originating from this collapsing bubble."

To prove his idea, Lohse created watertight theoretical models and equations, accurately demonstrating that a cavitation bubble was the only explanation for such a sound.

The shrimp had to be slightly annoyed

"But zoologists are not convinced by mathematical models," he says. "They wouldn't believe me." Lohse needed to perform some experiments with real shrimp to persuade them.

Using a high-speed camera (able to take 40,500 frames per second), a set of underwater microphones, and a paintbrush, Lohse's colleague, Michel Versluis, was able to deliver the goods.

Wait… a paintbrush?

Stimpson's snapping shrimp (Synalpheus stimpsoni) (Credit: CB Images/Alamy Stock Photo)
A pair of Stimpson's snapping shrimp (Synalpheus stimpsoni) (Credit: CB Images/Alamy Stock Photo)
To induce a snap, the shrimp had to be slightly annoyed, through tickling – and a paintbrush proved to be the perfect tickling stick. Only then could the data collection start.

As revealed by the high-speed videos, when the snapping shrimp's claw closes, one pincer has a protuberance that fits snugly within a hole on the other, like the internal workings of a tiny garlic crusher.

With a bang, the bubble explodes into a shower of tiny bubbles

While the claw is open, the shrimp contracts opposing muscles to ratchet up the tension – then it suddenly releases this tension so that the pincers tear through the water at close to 100km/h and the claw violently snaps shut.

But, at this point – silence. Lohse and Versluis picked up barely a murmur as the two pincers clacked together. The familiar loud "snap" actually came a fraction of a thousandth of a second later; a small but significant delay.

As the plunger on one pincer is forced into the socket on the other, a fast jet of water is ejected. "And high velocity means low pressure," says Lohse. Consequently, a zone of intense low pressure forms around the shrimp's claw.

Any small air bubbles in the vicinity – known as nuclei – are inflated by this change in pressure and follow the flow of water.

A shrimp goby with its attendant shrimp (Credit: Chris Gug/Alamy Stock Photo)
A shrimp goby with its attendant shrimp (Credit: Chris Gug/Alamy Stock Photo)
But when the bubbles move far enough away from the claw, they encounter a huge disparity in pressure between the water outside and the air inside them. The bubbles collapse under the strain.

It can stun small prey, and can even dismember and kill small invertebrates and fish

"This is happening really fast," says Anna von der Heydt who worked on the theoretical equations of the shrimp's cavitation bubbles. "The bubble growth and collapse happens in less than one millisecond [a thousandth of a second]."

With a bang, the bubble explodes into a shower of tiny bubbles, reverting back into the same infinitesimal nuclei that started it all.

The shockwave produced from bubble collapse is not only very loud, it is also extremely powerful. It can stun small prey, and can even dismember and kill small invertebrates and fish. Snapping shrimp have weaponised bubbles.

A pair of snapping shrimp (Alpheus sp.) (Credit: WaterFrame/Alamy Stock Photo)
A pair of snapping shrimp (Alpheus sp.) (Credit: WaterFrame/Alamy Stock Photo)
Like an underwater firework, the exploding bubble generates light as well as sound. By placing the shrimps in complete darkness and using a highly sensitive photodetector – and, of course, a paintbrush – Versluis could show that each bubble collapse coincides with the production of 50,000 photons.

I will never get rid of the name 'the shrimp guy'

In everyday language: it was dim. It was imperceptible to the human (and shrimp?) eye. But it was extremely hot, reaching temperatures that matched the surface of the sun, albeit very briefly and in a very small place.

This phenomenon needed a name: something similar to "sonoluminescence", the process of light emission from bubble cavitation. "We came up with the name 'shrimpoluminescence'," says Lohse. "We invented this name over a beer."

Today, Lohse and Versluis still work together at Twente University, studying the physics of fluids and cavitation. Their offices are next door. The four shrimp that they used in their experiments, though, have long since died.

"It's been 16 years," says Lohse, "but I will never get rid of the name 'the shrimp guy'."
They're pretty cool. In Australian waters the species are Mantis Shrimp, also known as Prawn Killers or. Thumb Splitters.

They can't be kept in fish tanks 'cause they destroy the glass, and their hit is so fast that it creates an intense heat and flash of light.
 

Alan79

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They're pretty cool. In Australian waters the species are Mantis Shrimp, also known as Prawn Killers or. Thumb Splitters.

They can't be kept in fish tanks 'cause they destroy the glass, and their hit is so fast that it creates an intense heat and flash of light.
I used to keep a few aquariums and had heard of Mantis shrimp. But these were something I hadn't heard of. It's amazing that nature has shaped these little guys as it has.
 

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When the universe was half the age it is now — around 7 billion years ago — two massive black holes crashed together.

This collision created a monster black hole almost 150 times the mass of our Sun.

The ripples it caused in the fabric of space-time reached Earth in May last year.

GW190521, as the colossal event has been named, is the most massive black hole collision we've ever directly detected.

And it's very different from previous black hole collisions picked up by the LIGO and Virgo gravitational wave detectors since 2015.

"This detection was really special because we got a few firsts that we hadn't known about before," said ANU's Susan Scott, chief investigator of the ARC Centre of Excellence for Gravitational Wave Discovery (OzGrav).
 

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When the universe was half the age it is now — around 7 billion years ago — two massive black holes crashed together.

This collision created a monster black hole almost 150 times the mass of our Sun.

The ripples it caused in the fabric of space-time reached Earth in May last year.

GW190521, as the colossal event has been named, is the most massive black hole collision we've ever directly detected.

And it's very different from previous black hole collisions picked up by the LIGO and Virgo gravitational wave detectors since 2015.

"This detection was really special because we got a few firsts that we hadn't known about before," said ANU's Susan Scott, chief investigator of the ARC Centre of Excellence for Gravitational Wave Discovery (OzGrav).
I love the idea of gravitational waves. It's like most relative gravity ideas. It can be hard to get your head around and hard to explain but the waves themselves are waves in reality itself. They cause every part of existence to stretch and shrink as the waves pass through.
 

Hacky McAxe

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Science shows for kids when I was a kid:

"I'm going to pour these two chemicals together and it'll foam up"

Science shows for kids now:

"let's explain Quantum Physics"

 

ASSASSIN

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I used to keep a few aquariums and had heard of Mantis shrimp. But these were something I hadn't heard of. It's amazing that nature has shaped these little guys as it has.
Are the Mantis shrimp also known as the pissing shrimp? Or is that another breed?
 

Hacky McAxe

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Are the Mantis shrimp also known as the pissing shrimp? Or is that another breed?
Pistol Shrimp?

Different species with different defence mechanisms. People often get the two mixed up though. That recent Jamie Foxx film talked about Pistol Shrimp but then described Mantis Shrimp.

Mantis Shrimp move extremely fast and their claw hit moves so fast that it breaks the sound barrier and emits light and heat.

Pistol Shrimp are smaller and slower but they have one of the most amazing mechanisms. One of their claws is basically a gun. They open cock the claw open and when another creature comes near they close the claw like a gun hammer firing. It's so fast and intense that it creates a bubble that's effectively a stun bullet. It shoots at the target and hits them with what's effectively a sonic and electrical charge that knocks them out. It's primarily used for defence against other shrimp rather than hunting like the Mantis Shrimp.

"Pistol Shrimp" is another name for the snapping shrimp that Alan posted about
 

ASSASSIN

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Pistol Shrimp?

Different species with different defence mechanisms. People often get the two mixed up though. That recent Jamie Foxx film talked about Pistol Shrimp but then described Mantis Shrimp.

Mantis Shrimp move extremely fast and their claw hit moves so fast that it breaks the sound barrier and emits light and heat.

Pistol Shrimp are smaller and slower but they have one of the most amazing mechanisms. One of their claws is basically a gun. They open cock the claw open and when another creature comes near they close the claw like a gun hammer firing. It's so fast and intense that it creates a bubble that's effectively a stun bullet. It shoots at the target and hits them with what's effectively a sonic and electrical charge that knocks them out. It's primarily used for defence against other shrimp rather than hunting like the Mantis Shrimp.

"Pistol Shrimp" is another name for the snapping shrimp that Alan posted about
I could of sworn it was pissing shrimp. Seen it on a food travel show.
 
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