5 Things You Didn't Know About Stephen Hawking

getty images
getty images

Stephen Hawking is undoubtedly one of the world's most recognizable theoretical physicist, but let's take a look at five things you might not know about the longtime Cambridge professor:

1. HE PUT HIS MONEY WHERE HIS MOUTH WAS

When Hawking thought he was right about a scientific theory, he didn't back down, and he wasn't afraid to wager on himself.

Perhaps the most famous of Hawking's bets came in 1997, when he found himself in an argument with fellow theoretical physicists Kip Thorne and John Preskill. Hawking and Thorne contended that the information carried in Hawking radiation in black holes must be "new," a notion that would have required rewriting quantum physics. Preskill, on the other hand, felt that it was the view of black holes that needed rewriting. Since Hawking had likened the fate of information in a black hole to "burning an encyclopedia," the men wagered a set of encyclopedias on the outcome of their argument.

In 2004, Hawking presented a paper that contradicted his previously held beliefs, so he conceded the bet and presented Preskill with a copy of Total Baseball, The Ultimate Baseball Encyclopedia.

This bet wasn't Hawking's first. In his bestseller A Brief History of Time, he described a similar bet he made with Thorne in 1975. Hawking had long been a believer in the existence of black holes, but he wanted an "insurance policy" that would give him some consolation if his theories turned out to be bunk. The wager: if black holes didn't exist, Thorne had to cough up a four-year subscription to the British satirical magazine Private Eye for Hawking as a consolation prize. If black holes existed, Hawking had to cover a one-year subscription to Penthouse for Thorne. Hawking eventually made good on his end of the wager and revealed that he had sent Thorne his skin-mag subscription "much to the outrage of Kip's liberated wife."

2. THE POPE DIDN'T ALWAYS SUPPORT THIS WORK

In 2006, Hawking revealed in a lecture that Pope John Paul II had discouraged the scientist from studying the beginning of the universe. According to Hawking, he was attending a cosmology conference at the Vatican when the Pope warned that while studying the universe was an acceptable pursuit, its origins were the work of God and shouldn't be explored.

Hawking took the Pope's grief in stride, though. He joked to his lecture audience that he was glad the Pope hadn't known about the paper Hawking had presented at the conference, which dealt with "“ you guessed it "“ the beginning of the universe. Hawking playfully explained, "I didn't fancy the thought of being handed over to the Inquisition like Galileo."

3. THERE WAS A STORY BEHIND HIS VOICE

Although Hawking was English, his computerized voice synthesizer made him speak with an American accent. What gives? The voice synthesizer Hawking used, a DECTalk DTC01, was actually a pretty old piece of equipment from 1986. The synthesizer was bulky and fragile, but Hawking had his reasons for not upgrading. He once said, "I keep it because I have not heard a voice I like better and because I have identified with it."

Hawking did briefly consider switching to a different machine that would have given him a French accent but said he decided against it because he thought his wife would divorce him. Hawking's voice box also got a chance to "sing" in 2009 on a A Glorious Dawn, a Jack White-produced vinyl single released as a tribute on what would have been Carl Sagan's 75th birthday.

4. HE RACKED UP A NUMBER OF SCREEN CREDITS.

How many scientists can add "Appeared on hit TV shows" to the bottom of their curriculum vitae? In 1994, Hawking made an appearance on Star Trek: The Next Generation, in which he played a hologram of himself who was locked in a poker game with holograms of Albert Einstein and Sir Isaac Newton.

In 1999 The Simpsons wanted to use Hawking in the episode "They Saved Lisa's Brain," Hawking agreed not only to allow the producers to use his image but to do his own voicework. Here's Hawking talking about his first appearance in Springfield:

Hawking would go on to do more guest spots on The Simpsons, and he also appeared on Futurama.

5. RICHARD BRANSON HELPED HIM FLOAT

In late 2006, Hawking publicly advocated for human colonization of other planets and declared that his next goal was to go into space. He even joked "Maybe Richard Branson will help me." In 2007, the billionaire entrepreneur made it happen. Branson covered all of the costs for Hawking to go on a flight that made the scientist the first quadriplegic to float in zero gravity. Here's video of the flight and Hawking talking about the experience:

13 Father's Day Gifts for Geeky Dads

Amazon/Otterbox/Toynk
Amazon/Otterbox/Toynk

When in doubt, you play the hits. Watches, flasks, and ties are all tried-and-true Father’s Day gifts—useful items bought en masse every June as the paternal holiday draws near. Here’s a list of goodies that put a geeky spin on those can’t-fail gifts. We’re talking Zelda flasks, wizard-shaped party mugs, and a timepiece inspired by BBC’s greatest sci-fi series, Doctor Who. Light the “dad” signal ‘cause it’s about to get nerdy!

1. Lord of the Rings Geeki Tikis (Set of Three); $76

'Lord of The Rings' themed tiki cups.
Toynk

If your dad’s equally crazy about outdoor shindigs and Tolkien’s Middle-earth, help him throw his own Lothlórien luau with these Tiki-style ceramic mugs shaped like icons from the Lord of the Rings saga. Gollum and Frodo’s drinkware doppelgängers each hold 14 ounces of liquid, while Gandalf the Grey’s holds 18—but a wizard never brags, right? Star Wars editions are also available.

Buy it: Toynk

2. Space Invaders Cufflinks; $9

'Space Invaders' cufflinks on Amazon
Fifty 50/Amazon

Arcade games come and arcade games go, but Space Invaders has withstood the test of time. Now Pops can bring those pixelated aliens to the boardroom—and look darn stylish doing it.

Buy it: Amazon

3. Legend of Zelda Flask; $18

A 'Legend of Zelda' flask
Toynk

Saving princesses is thirsty work. Shaped like an NES cartridge, this Zelda-themed flask boasts an 8-ounce holding capacity and comes with a reusable straw. Plus, it makes a fun little display item for gamer dads with man caves.

Buy it: Toynk

4. AT-AT Family Vacation Bag Tag; $12

An At-At baggage tag
ShopDisney

Widely considered one of the greatest movie sequels ever made, The Empire Strikes Back throws a powerful new threat at Luke Skywalker and the Rebellion: the AT-AT a.k.a. Imperial Walkers. Now your dad can mark his luggage with a personalized tag bearing the war machine’s likeness.

Buy it: ShopDisney

5. Flash Skinny Tie; $17

A skinny Flash-themed tie
Uyoung/Amazon

We’ll let you know if the Justice League starts selling new memberships, but here’s the next best thing. Available in a rainbow of super-heroic colors, this skinny necktie bears the Flash’s lightning bolt logo. Race on over to Amazon and pick one up today.

Buy it: Amazon

6. Captain America Shield Apron; $20

A Captain America themed apron
Toynk

Why let DC fans have all the fun? Daddy-o can channel his inner Steve Rogers when he flips burgers at your family’s Fourth of July BBQ. Measuring 31.5 inches long by 27.5 inches wide, this apron’s guaranteed to keep the cookout Hydra-free.

Buy it: Toynk

7. Doctor Who Vortex Manipulator LCD Leather Wristwatch; $35

A Doctor Who-themed watch
Toynk

At once classy and geeky, this digital timepiece lovingly recreates one of Doctor Who’s signature props. Unlike some of the gadgets worn on the long-running sci-fi series, it won’t require any fancy chronoplasm fuel.

Buy it: Toynk

8. Wonder Woman 3-Piece Grill Set; $21

Wonder Woman three-piece gill set
Toynk

At one point in her decades-long comic book career, this Amazon Princess found herself working at a fast food restaurant called Taco Whiz. Now grill cooks can pay tribute to the heroine with these high-quality, stainless steel utensils. The set’s comprised of wide-tipped tongs, a BBQ fork, and a spatula, with the latter boasting Wonder Woman’s insignia.

Buy it: Toynk

9. Harry Potter Toon Tumbler; $10

Glassware that's Harry Potter themed
Entertainment Earth

You can never have too many pint glasses—and this Father’s Day, dad can knock one back for the boy who lived. This piece of Potter glassware from PopFun has whimsy to spare. Now who’s up for some butterbeer?

Buy it: EntertainmentEarth

10. House Stark Men’s Wallet; $16

A Game of Thrones themed watch
Toynk

Winter’s no longer coming, but the Stark family's propensity for bold fashion choices can never die. Manufactured with both inside and outside pockets, this direwolf-inspired wallet is the perfect place to store your cards, cash, and ID.

Buy it: Toynk

11. Mr. Incredible “Incredible Dad” Mug, $15

An Incredibles themed mug
ShopDisney

Cue the brass music. Grabbing some coffee with a Pixar superhero sounds like an awesome—or dare we say, incredible?—way for your dad to start his day. Mom can join in the fun, too: Disney also sells a Mrs. Incredible version of the mug.

Buy it: ShopDisney

12. Star Wars phone cases from Otterbox; $46-$56

Star Wars phone cases from OtterBox.
Otterbox

If your dad’s looking for a phone case to show off his love of all things Star Wars, head to Otterbox. Whether he’s into the Dark Side with Darth Vader and Kylo Ren, the droids, Chewbacca, or Boba Fett, you’ll be able to find a phone case to fit his preference. The designs are available for both Samsung and Apple products, and you can check them all out here.

Buy it: Otterbox

13. 3D Puzzles; $50

3D Harry Potter puzzle from Amazon.
Wrebbit 3D

Help dad recreate some of his favorite fictional locations with these 3D puzzles from Wrebbit 3D. The real standouts are the 850-piece model of Hogwarts's Great Hall and the 910-piece version of Winterfell from Game of Thrones. If dad's tastes are more in line with public broadcasting, you could also pick him up an 890-piece Downton Abbey puzzle to bring a little upper-crust elegance to the homestead.

Buy it: Hogwarts (Amazon), Winterfell (Amazon), Downton Abbey (Amazon)

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Tear Gas vs. Pepper Spray: What’s the Difference?

This is probably pepper spray.
This is probably pepper spray.
Siberian Photographer/iStock via Getty Images

Pepper spray and tear gas are both non-lethal irritants that cause extreme burning of the eyes, nose, and throat—but there are a few key differences between the two substances.

For one, they’re created from different chemicals. According to biohazard remediation company Aftermath, the active ingredient in pepper spray is oleoresin capsicum, which comes from the compound that makes hot peppers so hot: capsaicin. If you’ve ever accidentally rubbed your eyes after chopping a chili pepper, you’ve gotten a very tiny taste of what it’s like to be sprayed with pepper spray. Tear gas, on the other hand, contains 0-Chlorobenzylidenemalononitrile (CS), 2-chlorobenzalmalononitrile (CN), or a similar artificial chemical. At room temperature, both of those chemicals are powdery solids, not gases—they’re mixed with liquids or gases so they can be dispersed in the air.

Delivery methods differ, too. Pepper spray often comes in an aerosol can, which shoots it in a stream, a mist, or some other relatively direct path (though it’s also available as a gel or foam). As the Berkeley Science Review explains, tear gas is mainly dispersed with a grenade, which releases the substance over a wide area when it explodes. Since the grenades can cover so much ground, law enforcement officers are more likely to use tear gas to try to break up a crowd, and civilians are more likely to carry pepper spray as a personal safety measure.

The immediate effects of the two substances are similar—burning sensation in mucous membranes, rise in blood pressure, difficulty breathing, runny nose, etc.—but tear gas can also cause nausea and vomiting in higher concentrations.

For more on tear gas, including what to do if you’re exposed to it, head here.

[h/t Aftermath]