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Category: cosmology – Page 245

Did the Big Bang happen?

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Physicists have many theories for the beginning of our universe: A big bang, a big bounce, a black hole, a network, a collision of membranes, a gas of strings, and the list goes on. What does this mean? It means we don’t know how the universe began. And the reason isn’t just that we’re lacking data, the reason is that science is reaching its limits when we try to understand the initial condition of the entire universe.

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The Poplawski paper about how the universe might have been born from a black hole is here: https://link.springer.com/article/10.1007/s10714-021-02790-7

00:00 Intro.
00:25 The Big Bang Theory.
03:47 Why So Many Other Theories?
04:53 The Problem With Cosmology.
07:30 The Importance of Simplicity.
10:57 Stories of Creation.
15:35 Sponsor Message

The Latest Webb Observations Don’t Disprove The Big Bang, But They Are Interesting

This isn’t what we see. What we observe is that more distant galaxies have a dimmer surface brightness than closer ones. The amount of dimming is proportional to the amount of redshift the galaxy has. You might think this proves that all those distant galaxies are speeding away from us, but it actually doesn’t. If those distant galaxies were speeding away, you’d have two dimming effects. The red shift and the ever-increasing distance. The Tolman test predicts that in a simple expanding universe, the surface brightness of galaxies should diminish proportional to both redshift and distance. We only see the effects of redshift.

This fact has led some to propose a static universe where light spontaneously loses energy over time. It’s the so-called tired light hypothesis, and it’s very popular among big bang opponents. If the universe is static and light is tired, then the Tolman test predicts exactly what we observe. Hence no big bang.

Back in 2014, Eric Lerner et al. published a paper making exactly this point. It caused a flurry of “Big Bang Dead!” articles in the popular media. The latest claims about Webb killing the big bang began with a popular article by the same Eric Lerner. So here we are. In fairness, back in 2014, the Hubble observations supported Lerner’s claim, and so do the latest Webb observations. But what Lerner conveniently omitted from his paper is that the Hubble and Webb observations also support the LCDM model.

The Oldest Fossil Radio Galaxy Discovered Yet Has Been Found Hiding in a Cluster

The oldest radio galaxy yet discovered is hidden in a cluster.

Astronomers claim to have found the oldest fossil radio galaxy yet discovered, hiding in a cluster. The brightest galaxy in the cluster erupted as a result of supermassive black hole activity, blowing massive bubbles of radio light into space, according to a report published by ScienceAlert.

“These newly discovered bubbles — known as radio lobes, or a radio galaxy — are the oldest of their kind we’ve ever seen,” claimed the astronomers’ team led by Surajit Paul and Savitribai Phule from Pune University in India.

A second team of astronomers led by Gopal Krishna of the University of Mumbai also discovered a pair of younger lobes that are linked to the same parent galaxy.

If we had been around and able to see into the heart of galaxy cluster Abell 980 around 260 million years ago, we may have seen something very spectacular indeed.

The brightest galaxy in the cluster erupted, the result of activity from its supermassive black hole, an event that would go on to blow massive bubbles emitting radio light out into space.

Continue reading “The Oldest Fossil Radio Galaxy Discovered Yet Has Been Found Hiding in a Cluster” | >

What is a wormhole?

Are you curious?

Imagine two towns on two opposite sides of a mountain. People from these towns would probably have to travel all the way around the mountain to visit one another. But, if they wanted to get there faster, they could dig a tunnel straight through the mountain to create a shortcut. That’s the idea behind a wormhole.

A wormhole is like a tunnel between two distant points in our universe that cuts the travel time from one point to the other. Instead of traveling for many millions of years from one galaxy to another, under the right conditions, one could theoretically use a wormhole to cut the travel time down to hours or minutes.

You’ll often see wormholes in science fiction as a way to travel across the Galaxy.

Wormholes explained: How these space-time shortcuts act like time machines

Imagine two towns on two opposite sides of a mountain. People from these towns would probably have to travel all the way around the mountain to visit one another. But, if they wanted to get there faster, they could dig a tunnel straight through the mountain to create a shortcut. That’s the idea behind a wormhole.

A wormhole is like a tunnel between two distant points in our universe that cuts the travel time from one point to the other. Instead of traveling for many millions of years from one galaxy to another, under the right conditions, one could theoretically use a wormhole to cut the travel time down to hours or minutes.

Because wormholes represent shortcuts through space-time, they could even act like time machines. You might emerge from one end of a wormhole at a time earlier than when you entered its other end.

TIMELAPSE OF FUTURE SPACECRAFT: 2025 — 3000+

A sci fi documentary looking at a timelapse of future spacecraft. From the future of AI spaceships, Starship orbital refuelling, and space station worlds, to Mars colonization and in-space manufacturing.

Other topics include: SpaceX and the launch of their fleet of Starships — waiting in parking orbit around Earth, ready for the launch window to open to Mars. NASA and the mission of landing on the Martian Moon Phobos. Advances in spacecraft technology for protecting humans during multi-year interstellar journeys.

While the year 2100 and beyond, brings wormhole exploration, artificial intelligence based planets, and the possible need for a stellar engine — to protect the solar system.

Main narration by: Alexander Masters (www.alexander-masters.com)

Starship Artwork – used with permission and licensed from:
Erc X: https://twitter.com/ErcXspace.
Caspar Stanley: https://twitter.com/Caspar_Stanley.
Alex Svan: https://twitter.com/AlexSvanArt.

Additional footage sourced from: SpaceX, NASA, ESO, Ken Crawford, Nick Risinger, Northrop Grumman, SpinLaunch, Redwire Space.

Continue reading “TIMELAPSE OF FUTURE SPACECRAFT: 2025 — 3000+” | >

Quantum heat pump: A new measuring tool for physicists

Physicists from TU Delft, ETH Zürich and the University of Tübingen have built a quantum scale heat pump made from particles of light. This device brings scientists closer to the quantum limit of measuring radio frequency signals, which may be useful in the hunt for dark matter. Their work will be published as an open-access article in Science Advances on Aug. 26.

If you bring two objects of different temperature together, such as putting a warm bottle of white wine into a cold chill pack, heat usually flows in one direction, from hot (the wine) to cold (the chill pack). And if you wait long enough, the two will both reach the same temperature, a process known in physics as reaching equilibrium: a balance between the heat flow one way and the other.

If you are willing to do some work, you can break this balance and cause heat to flow in the “wrong” way. This is the principle used in your refrigerator to keep your food cold, and in efficient heat pumps that can steal heat from the outside to warm your house. In their publication, Gary Steele and his co-authors demonstrate a quantum analog of a heat pump, causing the elementary quantum particles of light, known as , to move “against the flow” from a hot object to a cold one.

Behold! Telescope image captures a dusty dance from merging galaxies

NGC 7,727 will someday merge with a nearby galaxy — and intertwine their black holes in the process.

The galaxy’s violent past is written into its shape and composition, and the details are visible via telescope. This week, the European Southern Observatory released a new image of NGC 7,727 taken with the ground-based Very Large Telescope (VLT).

Captured in visible light with the VLT’s FOcal Reducer and low dispersion Spectrograph 2 instrument, streams of dust kicked up by the two merging galaxies can be seen spiraling around NGC 7727. Bright blue and purple clusters of stars dot the inner arms of the galaxy.

And its lopsided shape is no coincidence: as its two parent galaxies spun dusty circles around each other, the newly-formed NGC 7,727 came into being in a rather uneven way.