About the SA Blog Network  


Posts Tagged "cosmology"

@ScientificAmerican

Getting Ready for Scientific American Tweet-Up at the American Museum of Natural History

We’re counting down the days here until the Scientific American tweet-up at the American Museum of Natural History on Wednesday, January 18, starting at 6 p.m. Full details are on my earlier blog post. We’ll enjoy talks, a tour of the “Beyond Planet Earth” exhibition–and some conversations over cocktails. Attendance is free for followers of [...]

Keep reading »
Basic Space

How a new map of the early universe is like a hedgehog

On the back of a hedgehog...

A new method for investigating dark energy has allowed astronomers to peer further back into the past than ever before, revealing a universe that was very different to the one we live in today. Today’s universe is expanding. Not just that, its expansion is accelerating. Galaxies are not only getting further away from us all [...]

Keep reading »
Basic Space

CLASH of the Galaxy Clusters

Galaxy cluster MACS 1206 as seen by the Hubble Space Telescope (click for a bigger version). Credit: {link url="http://hubblesite.org/newscenter/archive/releases/2011/25/"}NASA, ESA, M. Postman (STScI), and the CLASH Team{/link}

Galaxies do not usually exist alone. They tend to bunch together in small groups, like the Local Group of galaxies in which the Milky Way sits, or larger groups called clusters. This is useful for cosmologists, as it gives them a chance to study one of the most elusive substances in the universe: dark matter. [...]

Keep reading »
Critical Opalescence

How Do You Count Parallel Universes? You Can’t Just Go 1, 2, 3, …

Cosmologists have been thinking for years that our universe might be just one bubble amid countless bubbles floating in a formless void. And when they say “countless,” they really mean it. Those universes are damned hard to count. Angels on a pin are nothing to this. There’s no unambiguous way to count items in an [...]

Keep reading »
Critical Opalescence

Is Dark Matter a Glimpse of a Deeper Level of Reality?

Two years ago several of my Sci Am colleagues and I had an intense email exchange over a period of weeks, trying to figure out what to make of a new paper by string theorist Erik Verlinde. I don’t think I’ve ever been so flummoxed by physicists’ reactions to a paper. Mathematically it could hardly [...]

Keep reading »
Guest Blog

Habitable and not-so-habitable exoplanets: How the latter can tell us more about our origins than the former

On 29th September this year, astronomers announced the discovery of an exoplanet called Gliese 581 g. This planet, they said, was exactly the right distance from its star for water to exist on its surface, with a good chance that it could hold an atmosphere. These two properties are very important when judging whether a [...]

Keep reading »
Life, Unbounded

Subatomic to Superhorizon – Abandon All Hope!

Contemplating vastness

                      Grasping for an understanding of the true scale of the cosmos is a vital part of how we try to conceptualize reality and our place among it all. But it’s tremendously difficult, whether we’re seeking that ‘oh wow’ moment, or trying to gain intuition [...]

Keep reading »
Life, Unbounded

The Stars Are Beginning To Go Out…

The galaxy NGC 1365 aglow with H-alpha light (Credit: ESO)

They really are. The universe is apparently well past its prime in terms of making stars, and what new ones are being made now across the cosmos will never amount to more than a few percent on top of the numbers already come and gone. This is the rather disquieting conclusion of a new and [...]

Keep reading »
Life, Unbounded

Black Holes to the Rescue

The birth of a galaxy. An overlay of the X-ray light (blue) and ultraviolet light (red) coming from a system 12 billion years ago (with thanks to Wil van Breugel and Ian Smail)

This post is the fourth in a series that accompanies the publication of my book ‘Gravity’s Engines: How Bubble-Blowing Black Holes Rule Galaxies, Stars, and Life in the Cosmos’ (Scientific American/FSG). Ten years ago the universe was in trouble. Or rather, our puny human theories about the nature of all the stars and galaxies in [...]

Keep reading »
Life, Unbounded

Black Holes: Incredibly Loud and Extremely Distant

CygA-

This post is the third in a series that accompanies the upcoming publication of my book ‘Gravity’s Engines: How Bubble-Blowing Black Holes Rule Galaxies, Stars, and Life in the Cosmos’ (Scientific American/FSG). In space it’s a good thing that you can’t hear black holes scream. Although some of the most incontrovertible evidence for the existence [...]

Keep reading »
Life, Unbounded

Black Holes are Everywhere

Holes are everywhere, if you look...

This post is the second in a series that accompanies the upcoming publication of my book ‘Gravity’s Engines: How Bubble-Blowing Black Holes Rule Galaxies, Stars, and Life in the Cosmos’ (Scientific American/FSG). Black holes, even the really hugely massive ones, are tiny – positively microscopic pinpricks scattered throughout the vastness of spacetime. Even the largest, [...]

Keep reading »
Life, Unbounded

Stellar Sands Help Enrich The Universe

It's a desert out there...(Image created from source material by: NASA, ESA and A.Zijlstra (UMIST, Manchester, UK) and Rosino (Wikipedia))

One of the most widely known and repeated astrophysical facts is that stars produce all the heavy elements that eventually make planets, shrubberies, and the likes of us. It’s absolutely true, but how exactly do they get those elements out into the universe to do all that? A major route is stellar explosion. When supernovae [...]

Keep reading »
Life, Unbounded

Encounter at Dawn: Stephen Hawking, me, and an ATM

A black hole lenses the light of the Milky Way in the background (Credit: Ute Kraus amd Axel Mellinger)

This weekend Stephen Hawking turns 70, an extraordinary physical accomplishment to add to an extraordinary list of physics accomplishments. Seeing this news reminded me of the the first time that I crossed paths with Hawking. I’d love to be able to say that it was in intellectual debate, an exchange of brilliant ideas, but in [...]

Keep reading »
Observations

Cosmos Study Dashes Hope for New Neutrino

Planck CMB intensity map

First particle physicists discovered “a boring old Standard Model Higgs boson,” as my colleague Michael Moyer put it, meaning that the particle hewed closely to theoretical predictions and offered little in the way of guidance to new and exciting physics. This week the European Space Agency’s Planck satellite gave a significant boost to cosmology’s own [...]

Keep reading »
Observations

Physicists Debate the Many Varieties of Nothingness

Helix Nebula

What is nothing? Sounds like a simple question—nothing is simply the absence of something, of course—until you begin to think about it. The other night the American Museum of Natural History hosted its 14th annual Asimov Memorial Debate, which featured five leading thinkers opining (and sparring, sometimes testily, but more on that later) about the [...]

Keep reading »
Observations

Lindau Nobel Laureate Meeting: From the Big Bang to the Big Controversy (aka Climate Change)

The first morning lecture series for the Lindau Nobel Laureate Meeting, which is focused on physics for this, its 62nd anniversary year, got off to a cosmic start, tracing the origins and evolution of the universe, before crashing back to Earth with a discussion of climate change. (You can read all our coverage this week, [...]

Keep reading »
Observations

Astronomers Identify Very Distant (But Not the Most Distant) Galaxy

distant galaxy 13 billion years ago

The universe is a big place, and by peering across it astronomers get to look back in time. A galaxy or supernova so far away that it takes two billion years for its light to reach us will be seen here as it appeared two billion years ago. Remarkably, today’s best telescopes can look across [...]

Keep reading »
Observations

The Digital Cosmos: A Brief Reading List

GeV Gamma Ray Emission Regions from NASA

Do the laws of physics emerge from the laws of information? Perhaps, according to two World Science Festival events I attended this weekend on the connection between computers and the cosmos. The first examined the insight that all the information about a three-dimensional world can be encoded onto a two-dimensional surface. Taking this notion to [...]

Keep reading »
Observations

The universe is no fluke, Pope Benedict XVI says

Pope Benedict

Why are we here? Many cosmologists think that everything—not just life on Earth but the planets, the stars, the entire observable universe—is a roll of the dice writ large. Other universes within a grander multiverse have entirely different properties, not to mention completely different laws of physics, based on different rolls of those cosmic dice. [...]

Keep reading »

More from Scientific American

Account Linking

Welcome, . Do you have an existing ScientificAmerican.com account?

Yes, please link my existing account with for quick, secure access.



Forgot Password?

No, I would like to create a new account with my profile information.

Create Account
X