What's a Color?

 What is color? It seems like a simple question at first, but when you think about it, the reality of what we're seeing is a pretty complex situation. Our human eyes sift through a small piece of the vast electromagnetic spectrum and translate it into every color of the rainbow. But there are other animals that see these same wavelengths in different ways, or even see colors beyond what we can perceive! And not all color is dependent on wavelengths of light: the brains of certain people, called synesthetes, work in ways that let them see colors tied to music, words, or other stimuli. Watch as host Alan Alda takes you on a surreal, scientific tour of the spectrum with the help of vision researcher Jay Neitz, along with neuroscientists David Eagleman, Kaitlyn Hova, and Bevil Conway.

See Also: “What Is Color?”

First Full 3D Model of Eta Carinae Nebula Created by Nasa Scientists

An international team of astronomers has developed a 3D model of a giant cloud ejected by the massive binary system Eta Carinae during its 19th century outburst. Eta Carinae lies about 7,500 light-years away in the southern constellation of Carina and is one of the most massive binary systems astronomers can study in detail. The smaller star is about 30 times the mass of the sun and may be as much as a million times more luminous. The primary star contains about 90 solar masses and emits 5 million times the sun's energy output. Both stars are fated to end their lives in spectacular supernova explosions.

A new shape model of the Homunculus Nebula reveals protrusions, trenches, holes and irregularities in its molecular hydrogen emission. The protrusions appear near a dust skirt seen at the nebula's center in visible light (inset) but not found in this study, so they constitute different structures.

Image Credit: 

NASA Goddard (inset: NASA, ESA, Hubble SM4 ERO Team)

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See Also:

•  Astronomers Bring The Third Dimension To A Doomed Star's Outburst

Algebraic Topology

A first course in Algebraic Topology, with emphasis on visualization, geometric intuition and simplified computations. Given by Assoc Prof N J Wildberger at UNSW. The really important aspect of a course in Algebraic Topology is that it introduces us to a wide range of novel objects: the sphere, torus, projective plane, knots, Klein bottle, the circle, polytopes, curves in a way that disregards many of the unessential features, and only retains the essence of the shapes of spaces. What does this exactly mean? That is a key question... The course has some novel features, including Conway's ZIP proof of the classification of surfaces, a rational form of turn angles and curvature, an emphasis on the importance of the rational line as the model of the continuum, and a healthy desire to keep things simple and physical. We try to use pictures and models to guide our understanding.

See Also:

• Algebraic Topology

Proofing BICEP2

Inflation—the hypothesis that the Universe underwent a phase of superluminal expansion in a brief period following the big bang—has the potential of explaining, from first principles, why the Universe has the structure we see today. It could also solve outstanding puzzles of standard big-bang cosmology, such as why the Universe is, to a very good approximation, flat and isotropic (i.e., it looks the same in all directions). Yet we do not yet have a compelling model, based on fundamental particle physics principles, that explains inflation. And despite its explanatory power and a great deal of suggestive evidence, we still lack an unambiguous and direct probe of inflation. Theorists have developed different models for inflation, which all share a common, robust prediction: Inflation would have created a background of gravitational waves that could have an observable effect. These waves would cause subtle, characteristic distortions of the cosmic microwave background (CMB)—the oldest light in the Universe, released when photons decoupled from matter and the Universe became transparent to radiation. Viewpoint: Peering Back to the Beginning of Time

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First Direct Evidence of Cosmic Inflation

Almost 14 billion years ago, the universe we inhabit burst into existence in an extraordinary event that initiated the Big Bang. In the first fleeting fraction of a second, the universe expanded exponentially, stretching far beyond the view of our best telescopes. All this, of course, was just theory.

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 LSC Congratulates BICEP2 Colleagues

 

18 March 2014 - The BICEP2 Collaboration result, if confirmed, is a landmark discovery in cosmology, allowing us for the first time to peer back almost to the moment of the Big Bang through the observation of the imprint of primordial gravitational waves on the cosmic microwave background. The LIGO Scientific Collaboration congratulates our BICEP colleagues on their accomplishment and will further follow discoveries and implications of these observations with great interest. - See more at: http://www.ligo.org/news/bicep-result.php#sthash.mJlemItG.dpuf

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See Also:

• The Inverse Problem. Sorry, we don’t have experimental evidence for quantum gravity.
• Detection of B-Mode Polarization at Degree Angular Scales by BICEP2
• BICEP2′s Cosmic Polarization: Published, Reduced in Strength(Lawrence M. Krauss,) 
  Published June 19, 2014  |  Physics 7, 64 (2014)  |  DOI: 10.1103/Physics.7.64

Puffing in Large Scale Interactions

This combination of three wavelengths of light from NASA's Solar Dynamics Observatory shows one of the multiple jets that led to a series of slow coronal puffs on Jan. 17, 2013. The light has been colorized in red, green and blue.

Image Credit: Alzate/SDO

A suite of NASA's sun-gazing spacecraft have spotted an unusual series of eruptions in which a series of fast puffs forced the slow ejection of a massive burst of solar material from the sun's atmosphere. The eruptions took place over a period of three days, starting on Jan. 17, 2013. Nathalia Alzate, a solar scientist at the University of Aberystwyth in Wales, presented findings on what caused the puffs at the 2014 Royal Astronomical Society's National Astronomy Meeting in Portsmouth, England. See: Puffing Sun Gives Birth To Reluctant Eruption

From the Mathematics of Supersymmetry to the Music of Arnold Schoenberg

Published on Jun 28, 2014

https://perimeterinstitute.ca/videos/...

The concept of supersymmetry, though never observed in nature, has driven a great deal of research in theoretical physics over the past several decades. Much has been learned through this research, but many unresolved questions remain. This presentation will describe how these questions can lead one down a surprising path: toward the dodecaphony of Austrian composer Arnold Schoenberg.

Speaker(s):
S. James Gates Jr.
Collection/Series:
Perimeter Institute Public Lecture Series

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See Also:

• TVO S James Gates on Does Reality have a Genetic Basis 
• Adinkra Symbols(physics) 
• Adinkras and Benoit Mandelbrot

On Superposition

Published on Jun 18, 2014

MIT 8.04 Quantum Physics I, Spring 2013
View the complete course: http://ocw.mit.edu/8-04S13
Instructor: Allan Adams

In this lecture, Prof. Adams discusses a series of thought experiments involving "box apparatus" to illustrate the concepts of uncertainty and superposition, which are central to quantum mechanics. The first ten minutes are devoted to course information.

License: Creative Commons BY-NC-SA
More information at http://ocw.mit.edu/terms
More courses at http://ocw.mit.edu

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See Also:

• Quantum Mechanics Open Course from MIT

LHC Sound

Sonification is the process of creating sounds that carry information. Musical compositions carry information in the sense that they often describe a place, a time or a feeling; the associations we make between sonic properties such as pitch and physical properties such as speed or size, come to us without effort. The grand aim of the LHCsound project is to ‘dorkify’ the process of encoding information in sound. Our attempts to capture the behaviour of the recently discovered Higgs boson in sounds are presented for your wonder and bafflement. SEE: Lily Asquith

What is Your Theory On Blackhole Radiation?

MSU Professor Chris Adami has found the solution to a long-standing problem with Stephen Hawking's black hole theory. In a groundbreaking study recently published in the journal Classical and Quantum Gravity, Adami found that various types of information, as specific as matter or particles, or as obscure as the contacts in your mobile phone or the contents of a secret diary, never disappear in the black hole to begin with, effectively solving the black hole information paradox of Hawking's theory. See: Plugging the Hole in Hawking's Black Hole Theory

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Why are Black Holes useful? Which are the quantum properties of space and time? And what happens to a Black Hole when it gets older? Assistant Professor Sabine Hossenfelder and Professor Lárus Thorlacius at Nordita talk about why they want to find answers to questions like these. See: Research Presentation: Quantum Gravity and Black Hole Physics Research at Nordita

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See Also:

• Black holes, quantum information, and the foundations of physics
• The black-hole information paradox, complementarity, and firewalls by Leonard Susskind 
•  Do Black Holes Destroy Information?

Black holes, quantum information, and the foundations of physics

Volume 66, Issue 4, April 2013

Quantum mechanics teaches that black holes evaporate by radiating particles—a lesson indicating that at least one pillar of modern physics must fall. See: Black holes, quantum information, and the foundations of physics by Steven B. Giddings, in Physics Today, April 2013

Based on an image from NASA/CXC/M.Weiss

Citation: Phys. Today 66, 4, 30 (2013); http://dx.doi.org/10.1063/PT.3.1946

Figure 1. The spacetime geometry of the Schwarzschild black hole solution can be depicted in different ways. In this representation, ingoing light rays always travel along ingoing lines heading toward the top and left at 45°; outgoing light rays asymptotically approach 45° lines at large radius r. Massive particles, with their slower speeds, must travel within the light cones (blue) between outgoing and ingoing light rays, as illustrated by the red path. No light ray can escape to infinity from inside the vertical dotted line, the horizon located at the mass-dependent Schwarzschild radius R(M). Instead, any trajectory beginning inside the horizon is pulled to a central point, the singularity at r = 0, where spacetime curvature becomes infinite.

Citation: Phys. Today 66, 4, 30 (2013); http://dx.doi.org/10.1063/PT.3.1946

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