Tag Archives: Brian Greene

Brian Greene talks multiverses at Town Hall Seattle

If there’s such a thing as a celebrity theoretical physicist, Brian Greene is it, and he packed the city’s premiere lecture hall at Town Hall Seattle Wednesday evening for a talk titled, “Is Ours the Only Universe?” The talk helped sell many copies of Greene’s latest book, The Hidden Reality: Parallel Universes and the Deep Laws of the Cosmos, and likely also led to a spike in aspirin sales as many of us, whose ideas of parallel universes are limited to evil Spock with a beard, tried to recover from getting our heads around quantum mechanics, general relativity, string theory, and the notion of exact copies of ourselves a cajillion light years away pondering the same concepts.

Greene noted that parallel universes are something of a logical progression of the Copernican revolution that started when Copernicus suggested that the Earth was not at the center of the universe.

“The ideas that we’re thinking about today suggest that even the universe is not the center of the universe,” Greene said. “The universe is not the center of a wider cosmic landscape that we call the multiverse.

The Hidden Reality“These are speculative ideas that we’re talking about here tonight,” he added. “We don’t know that this is true.”

Greene says a big part of the puzzle is that the Big Bang theory leaves out a key piece of information: Just what was the bang?

“The Big Bang theory doesn’t tell us what banged or how it banged or if it even banged,” he explained. “It only tells us that a split second after something occurred, the universe continued to expand and cool down allowing structures like stars and galaxies ultimately to coalesce. We’ve been trying to fill in what happened at the beginning; what the bang was.”

One theory posits that powerful repulsive gravity many have triggered many outbursts, so that the Big Bang was not a unique event.

“Our universe would be the aftermath of one of those big bangs, but other universes could be the outcomes of their big bangs,” Greene said. “This is known as the inflationary multiverse and it’s one of the ways in which our universe could possibly be one of many.”

Another fascinating theory is that there may be infinite numbers of universes with exact copies of us out there. It’s called the Quilted Multiverse.

Brian Greene

Brian Greene spoke at Town Hall Seattle Feb. 2.

“In any finite region of space there can only be a finite amount of matter,” Greene explained. “In fact, by a little bit of quantum mechanics, there only are finitely many distinct configurations that that matter can assume.”

He used a deck of cards as an example. There are only so many cards, so if you keep shuffling long enough, the same arrangement of the deck is bound to repeat. Apply the same logic to the universe.

“If space goes on infinitely far, then the configurations of matter have to repeat too, because there are only finitely many different configurations that are possible,” Greene argued.

“If the configurations of particles of matter agree here and in some distant region, what would that mean? Well, we here are just a configuration of particles. We just are particles that make up you and me and everyone else in this room. So, if the particle configuration repeats out there, then we are out there. Copies of us are out there. In fact, if space goes on infinitely farther, infinitely many copies of us are out there in rooms like this having this conversation.”

It all depends on the assumption that space is infinite, and that quantum mechanics applies in the same way in the far reaches.

String theory started to gain momentum during the 1990s.

“The big puzzle for many, many years was that gravity as described by Einstein’s general relativity proves incompatible with the mathematics of quantum physics,” Greene said. “It’s as if you have one set of laws that work for stars and galaxies, another set of laws that do work well for molecules, atoms, and subatomic particles, but any time these two laws come together, the math just falls apart and becomes inconsistent.”

Many scientists assail the concept as unprovable. Greene says the math works.

“There’s no experimental evidence for string theory at all,” he said. “Zero. The reason we have some confidence that this is an interesting idea to pursue is because we believe in quantum mechanics; that is unassailable. We believe in the general theory of relativity; that is unassailable. We believe that the universe has to be governed by a consistent set of laws. Without string theory, quantum mechanics and general relativity are inconsistent. For us, that’s a very powerful reason for believing string theory may be going in the right direction, because it makes them compatible. That is no small feat.”

It was an interesting and thought-provoking evening with a celebrity theoretical physicist.


Bolden visit tops Seattle astronomy calendar for week of Jan. 31

Charlie Bolden

NASA administrator and former astronaut Charle Bolden will be in Seattle Saturday to participate in a panel discussion on African-Americans in aerospace, part of the observance of Black History Month at the Museum of Flight. Photo: NASA.

NASA administrator and former astronaut Charlie Bolden will be in Seattle Saturday to participate in a panel discussion on African-Americans in Aerospace, part of the Museum of Flight‘s observance of Black History Month. Other panelists include former Tuskegee Airman Ed Drummond; Lt. Col. Kimberly Scott, an Alaska Airlines pilot and U.S. Air Force Reserve C-17 pilot; Lt. Col. Rod Lewis, commander of the C-17 squadron at Joint Base Lewis-McChord; and Alaska Airlines Capt. Michael Swanigan. U.S. Air Force Deputy Inspector General Maj. Gen. Harold “Mitch” Mitchell will moderate the discussion. The event begins at 2 p.m. Saturday, Feb. 5, and is free with museum admission.

More MOF events
Feb. 3 is the monthly Free First Thursday at the Museum of Flight. Enjoy the exhibits at no charge from 5 p.m. until 9 p.m.

Saturday and Sunday the museum’s Weekend Family Workshops will be about the Saturn V. Participants will learn about the rocket that took the astronauts to the Moon, and will build their own models of the Saturn V. Programs are at 11 a.m. and 1 p.m. Feb. 5 and 6.

Is ours the only universe?
The notion of a parallel universe used to be strictly science fiction stuff. (I liked the Star Trek episode with the evil, bearded Spock!) Yet recent discoveries in physics and cosmology have led some scientists to conclude that our universe may be one among many. Wednesday, Feb. 2 at Town Hall Seattle physicist Brian Greene, author of The Hidden Reality: Parallel Universes and the Deep Laws of the Cosmos, explores different “multiverse” proposals: one parallel world in which you have an infinite number of doppelgängers, each reading this sentence in a distant universe; one that endlessly cycles through time; or one that might be hovering millimeters away—invisibly. The talk begins at 7:30 p.m. in the Great Hall of Town Hall Seattle.

From hot gas to cold stars
The Engage! Science Speakers Series kicks off a new season Wednesday with a talk by University of Washington Ph.D. student Charlotte Christensen about how she uses computer simulations to model the formation of stars and planetary systems from free-floating molecular hydrogen. Christensen gave a similar presentation last year. The talk begins at 7 p.m. Feb. 2 in Room 075 of Johnson Hall on the UW Seattle campus.

The dark side of the universe
Weber State University astrophysicist Shane Larson will give a talk on dark matter at this month’s meeting of the Spokane Astronomical Society. The meeting begins at 7:30 p.m. Friday, Feb. 4, in room 225 of building #24 at Spokane Falls Community College.