The Boston Citgo sign, all 3,600 square LED feet of which has served as the backdrop to Red Sox games since 1965, is now officially a "pending landmark."

Spanish Surrealist Salvador Dalí spent much of the 1940s in the U.S., avoiding World War II and its aftermath. He was a well-known fixture on the art scene in Monterey, Calif. — and that's where the largest collection of Dalí's work on the West Coast is now open to the public.

Copyright 2016 Fresh Air. To see more, visit Fresh Air.

The middle of summer is when the surprises in publishing turn up. I'm talking about those quietly commanding books that publishers tend to put out now, because fall and winter are focused on big books by established authors. Which brings us to The Dream Life of Astronauts, by Patrick Ryan, a very funny and touching collection of nine short stories that take place in the 1960s and '70s around Cape Canaveral, Fla.

When the United Kingdom voted to leave the European Union last month, the seaside town of Port Talbot in Wales eagerly went along with the move. Brexit was approved by some 57 percent of the town's residents.

Now some of them are wondering if they made the wrong decision.

The June 23 Brexit vote has raised questions about the fate of the troubled Port Talbot Works, Britain's largest surviving steel plant — a huge, steam-belching facility that has long been the town's biggest employer.

Solar Impulse 2 has landed in Cairo, completing the penultimate leg of its attempt to circumnavigate the globe using only the power of the sun.

The trip over the Mediterranean included a breathtaking flyover of the Pyramids. Check it out:

President Obama is challenging Americans to have an honest and open-hearted conversation about race and law enforcement. But even as he sits down at the White House with police and civil rights activists, Obama is mindful of the limits of that approach.

"I've seen how inadequate words can be in bringing about lasting change," the president said Tuesday at a memorial service for five law officers killed last week in Dallas. "I've seen how inadequate my own words have been."

Mice watching Orson Welles movies may help scientists explain human consciousness.

At least that's one premise of the Allen Brain Observatory, which launched Wednesday and lets anyone with an Internet connection study a mouse brain as it responds to visual information.

The FBI says it is giving up on the D.B. Cooper investigation, 45 years after the mysterious hijacker parachuted into the night with $200,000 in a briefcase, becoming an instant folk figure.

"Following one of the longest and most exhaustive investigations in our history," the FBI's Ayn Dietrich-Williams said in a statement, "the FBI redirected resources allocated to the D.B. Cooper case in order to focus on other investigative priorities."

This is the first in a series of essays concerning our collective future. The goal is to bring forth some of the main issues humanity faces today, as we move forward to uncertain times. In an effort to be as thorough as possible, we will consider two kinds of threats: those due to natural disasters and those that are man-made. The idea is to expose some of the dangers and possible mechanisms that have been proposed to deal with these issues. My intention is not to offer a detailed analysis for each threat — but to invite reflection and, hopefully, action.

Pages

Universe Or universe? It All Depends On The Multiverse

Feb 20, 2013
Originally published on February 28, 2013 12:41 pm

Sometimes behind what appears to be a mere grammatical issue hides a much deeper question of meaning.

The reader can easily check, after glancing at a handful of books and articles, including here at 13.7, that the word "universe" sometimes is capitalized and sometimes not. How is that decided, exactly? And who decides it? A choice is being made every time an author (or, more realistically, an editor) refers to the cosmos as "Universe" or as "universe." Let's ponder the reasoning behind this choice.

The most common position and, in my opinion, the worst, is to simply adopt "universe" indiscriminately. [Editor's note: That's largely what we've done here on 13.7, until today.] But what universe is this, exactly?

According to modern cosmological theories, and the burgeoning field of philosophical cosmology, we must be careful when we refer to the cosmos. There are several "universes" and so a distinction is essential for clarity.

Let's anchor our discussion on the most concrete knowledge we have, our observations. This is a choice already, one that shows my own preference to stay close to the spirit of the physical sciences, that is, to what is empirically validated.

We know that the information we can obtain about the cosmos, what we can "see," is limited in two ways. First, since nothing travels faster than light, information from a far away object like a galaxy takes time to reach us. Second, the cosmos we live in is time limited, starting 13.7 billion years ago in the event we call Big Bang (capitalized or not? [Editor's Note: Not. But we can change that policy today, too!]).

Putting the two together, we conclude that, at most, we can receive information (in the form of electromagnetic radiation — light, radio waves, etc.) from objects that emitted it 13.7 billion years ago. A bit more precisely, since the first stars and galaxies appeared around 200 million years after the "bang," our limit is for objects that emitted information some 13.5 billion years ago.

What exists beyond this information boundary — called the "horizon" — is inaccessible to us. (There are different kinds of "horizon," but we will stick with this one for clarity.) So, we can talk of the "observable universe," that comprises everything that we can measure (and what we can't yet). This part of the cosmos, that we know is out there, I like calling the Universe, since it's a concrete entity that includes all that we can know. Its boundary, the horizon, sits at a distance of about 46 billion light-years from us, the distance traveled by light in 13.7 billion years. (Why not 13.7 billion light-years away? Because the ongoing cosmic expansion gives light a boost, increasing its traveled distance by roughly a factor of three.)

But the Universe doesn't necessarily end at the boundary of what we can see. Very possibly, it extends beyond the measurable.

In fact, from a different vantage point in space, the observable universe will extend into different regions, that, like partially overlapping soap bubbles, may or not include ours. This is somewhat like the horizon we see from a beach; we know the sea goes on even if we can see it directly.

This continuation of the cosmos beyond the visible into regions which, presumably, are not so different from what's within our Universe, I call the universe. I don't think it deserves the "U" because we can only infer its existence and don't really know what's there. We can speculate that what's beyond the horizon won't be very different from what we see within it, but we can't be sure. (Unless we wait a real long time ... ) According to this choice, despite the "u," the universe contains the Universe.

Is that logical? You be the judge. It's hard to say when you don't have all the facts in hand.

Regardless, we must continue on. After all, today we speculate that the universe may not be unique, but part of a vast entity called the "multiverse." The multiverse itself may contain an enormous number of universes, possibly even an infinite number of them, although infinite is not something we can ever measure. We just don't know if the multiverse exists.

Worse, it seems to be impossible to confirm its existence, given that it naturally extends well beyond our Universe. At most, as some colleagues have calculated, we may obtain information of neighboring universes, if they have collided with ours in the past. (So far, we don't have anything indicative that this has happened.) Even so, to know of a neighbor or two is not the same as knowing about a country or a continent with hundreds of millions of people, or of an infinite multiverse. Concretely, we only have our Universe, even if our ideas may fly boundless across expanses beyond what we know.

Not a bad deal, really, given that we know so little of what's going on right here within our own cosmic information bubble.


You can keep up with more of what Marcelo is thinking on Facebook and Twitter: @mgleiser

Copyright 2013 NPR. To see more, visit http://www.npr.org/.