Post has attachment
What If the Big Bang Wasn't the Beginning? New Study Proposes Alternative
Was the universe created with a Big Bang 13.7 billion years ago, or has it been expanding and contracting for eternity? A new paper, inspired by alternative explanations of the physics of black holes, explores the latter possibility, and rejects a core tenant of the Big Bang hypothesis.

The universal origin story known as the Big Bang postulates that, 13.7 billion years ago, our universe emerged from a singularity — a point of infinite density and gravity — and that before this event, space and time did not exist (which means the Big Bang took place at no place and no time).

However, there is no direct evidence of the original singularity. (Collecting information from that first moment of expansion is impossible with current methods.) In the new paper, Brazilian physicist Juliano Cesar Silva Neves argues that the original singularity may never have existed.

Read the article:

#physics #BigBang #science #blackhole #universe

Post has attachment
What's a calorimeter?
Calorimeters measure the energy a particle loses as it passes through the detector. It is usually designed to stop entire or “absorb” most of the particles coming from a collision, forcing them to deposit all of their energy within the detector. Calorimeters typically consist of layers of “passive” or “absorbing” high-density material – for example, lead – interleaved with layers of an “active” medium such as solid lead-glass or liquid argon.

Electromagnetic calorimeters measure the energy of electrons and photons as they interact with matter. Hadronic calorimeters sample the energy of hadrons (particles that contain quarks, such as protons and neutrons) as they interact with atomic nuclei. Calorimeters can stop most known particles except muons and neutrinos.

The components of the ATLAS calorimetry system are: the Liquid Argon (LAr) Calorimeter and the Tile Hadronic Calorimeter.


Photo: portion of the Atlas Electromagnetic Calorimeter, CERN- I've seen at Museo Nazionale Scienza e Tecnologia Leonardo da Vinci in Milan.

#physics #calorimeter #Atlas #science #CERN

Post has attachment
Scientists Are Close to Detecting the Elusive Tetraquark Particle
It’s been 100 years since scientists first split open the atom and realized it was not the smallest thing to exist. It’s been more than 50 years since they started to suspect that the atom’s components— protons, neutrons, and electrons—weren’t either. Protons and neutrons have components of their own, called quarks, which are particles so tiny they’re almost impossible to study.

Electrons and positrons are not made up of quarks. They are in a separate "family" of particles known as leptons. Leptons and quarks are "fundamental" (indivisible) particles. Leptons do not experience the "strong" or "hadronic" force that protons and neutrons do.

A combination of three quarks creates a hadron, which, when stable, we know as a proton or neutron. But a combination of four quarks is something scientists have never been able to prove exists. That would be the tetraquark, which scientists have been chasing without success since the 1960s.

Now, researchers are about to publish what they say is proof that the tetraquark exists, that it’s stable, and that they can generate it in the Large Hadron Collider at the CERN particle physics lab in Switzerland.

Story via live science

#physics #tetraquark #research #science

Post has attachment
Soap films have the remarkable property of self-healing. A water drop, like the one shown below, can pass through a bubble (repeatedly!) without popping it. This happens thanks to surfactants and the Marangoni effect.

Surfactants are molecules that lower the surface tension of a liquid and congregate along the outermost layer of a soap film. When water breaks through the soap film, its lack of surfactants causes a higher surface tension locally. This triggers the Marangoni effect, in which flow moves from areas of low surface tension toward ones of high surface tension.

That carries surfactants to the region where the drop broke through and helps stabilize and heal the soap film. Incidentally, the same process lets you stick your finger into a bubble without popping it as long as your hand is wet!

What is Marangoni Effect? Read & Learn:

What are surfactants? Read & Learn:

Image credit: G. Mitchell and P. Taylor

Story via FYFD

#physics #MarangoniEffect #surfactants #soapfilms #fluidDynamics #science
Animated Photo

Post has attachment
Carbon nanotube “yarn” generates electricity when stretched
The piezoelectric and triboelectric generators that are currently used to harvest electricity from material stress and friction are both expensive and inefficient. Now, carbon nanotubes spun into yarn and then twisted into a spring-like shape have been shown to be a combination of the two types of generators.

The researchers tested the yarn in a variety of environments, including stretched between a weight and a float in the ocean, attached to a polymer that contracts when heated, and even into a shirt that produced electricity as the person wearing it breathed. While the efficiency of the electricity generation isn't particularly high, the weight to energy ratio makes it an interesting option for continued investigation for a variety of uses.

Source & further reading:

Gif: When the yarn is stretched, the LED lights up.
Video source:

h/t Physics Today

#science #physics #nanotubes #electricity #research
Animated Photo

Post has attachment
Have we detected a new flavor of gravitational wave?
Speculation based on hints from researchers on twitter is running rampant that LIGO has detected gravitational waves from a source other than colliding black holes. LIGO's current observational run ends on 25 August and any signals that were detected during the run will be announced soon thereafter.

Story via New Scientist

#physics #LIGO #neutronstars #gravitationalWaves #science
2 Photos - View album

Post has attachment
Supermassive black holes feed on cosmic jellyfish
Observations of “Jellyfish galaxies” with ESO’s Very Large Telescope have revealed a previously unknown way to fuel supermassive black holes. It seems the mechanism that produces the tentacles of gas and newborn stars that give these galaxies their nickname also makes it possible for the gas to reach the central regions of the galaxies, feeding the black hole that lurks in each of them and causing it to shine brilliantly.

This picture of one of the galaxies, nicknamed JO204, from the MUSE instrument on ESO’s Very Large Telescope in Chile, shows clearly how material is streaming out of the galaxy in long tendrils to the lower-left. Red shows the glow from ionised hydrogen gas and the whiter regions are where most of the stars in the galaxy are located. Some more distant galaxies are also visible.

Story via ESO


Image Credit:
ESO/GASP collaboration

#science #astrophysics #blackholes #jellyfishgalaxy #research

Post has attachment
Milky Way's origins are not what they seem
In a first-of-its-kind analysis, Northwestern University astrophysicists have discovered that, contrary to previously standard lore, up to half of the matter in our Milky Way galaxy may come from distant galaxies. As a result, each one of us may be made in part from extragalactic matter.

Using supercomputer simulations, the research team found a major and unexpected new mode for how galaxies, including our own Milky Way, acquired their matter: intergalactic transfer. The simulations show that supernova explosions eject copious amounts of gas from galaxies, which causes atoms to be transported from one galaxy to another via powerful galactic winds. Intergalactic transfer is a newly identified phenomenon, which simulations indicate will be critical for understanding how galaxies evolve.

"Given how much of the matter out of which we formed may have come from other galaxies, we could consider ourselves space travelers or extragalactic immigrants," said Daniel Anglés-Alcázar, a postdoctoral fellow in Northwestern's astrophysics center, CIERA (Center for Interdisciplinary Exploration and Research in Astrophysics), who led the study. "It is likely that much of the Milky Way's matter was in other galaxies before it was kicked out by a powerful wind, traveled across intergalactic space and eventually found its new home in the Milky Way."

Source and further reading:

Journal article:

Photo via Reddit
Photo credit: Fred Herrmann

#science #physics #intergalactictransfer #matter #space #research #astrophysics

Post has attachment
The quantum carrier pigeon that wasn’t there
Counterfactual communication is a puzzling quantum concept in which two parties can exchange information without any photon or other physical messenger passing between them.

Here's how it's done:

Journal article:

#physics #science #counterfactualcommunication #research

Post has attachment
What is quantum teleportation and more importantly, what it isn't?
Quantum teleportation transfers the quantum state of one particle onto another, identical particle, and at the same time erases the state in the original. This situation can’t be meaningfully distinguished from one in which the original particle itself has been moved to the target location: that transport has not really happened, but to all appearances it might as well have.

Crucially, however, this works only if you do not know what ‘information’ you are sending — that is, what the quantum state of the original particle actually is.

Teleportation of a quantum state uses the phenomenon of quantum entanglement as a means of transmission. When two or more particles are entangled, their quantum states are interdependent, no matter how far apart they are. In effect, they act as a single quantum object, described by a single wavefunction — the mathematical construct that encodes all the quantum properties of the object.

Here's a good explainer of what quantum teleportation is, and perhaps more importantly, what it isn't via Nature:

Infographic via JPL/NASA

#science #physics #quantumteleportation #JPL
Wait while more posts are being loaded