When Did People Start Using Money?

By Chapurukha Kusimba, American University | June 20, 2017 1:49 pm
money

(Credit: Shutterstock)

Sometimes you run across a grimy, tattered dollar bill that seems like it’s been around since the beginning of time. Assuredly it hasn’t, but the history of human beings using cash currency does go back a long time – 40,000 years.

Scientists have tracked exchange and trade through the archaeological record, starting in Upper Paleolithic when groups of hunters traded for the best flint weapons and other tools. First, people bartered, making direct deals between two parties of desirable objects. Read More

CATEGORIZED UNDER: Living World, Top Posts

Creating a Universe in the Lab? The Idea Is No Joke

By Zeeya Merali | June 19, 2017 1:15 pm
universe

(Credit: Shutterstock)

Physicists aren’t often reprimanded for using risqué humor in their academic writings, but in 1991 that is exactly what happened to the cosmologist Andrei Linde at Stanford University. He had submitted a draft article entitled ‘Hard Art of the Universe Creation’ to the journal Nuclear Physics B. In it, he outlined the possibility of creating a universe in a laboratory: a whole new cosmos that might one day evolve its own stars, planets and intelligent life. Near the end, Linde made a seemingly flippant suggestion that our Universe itself might have been knocked together by an alien ‘physicist hacker’. The paper’s referees objected to this ‘dirty joke’; religious people might be offended that scientists were aiming to steal the feat of universe-making out of the hands of God, they worried. Linde changed the paper’s title and abstract but held firm over the line that our Universe could have been made by an alien scientist. ‘I am not so sure that this is just a joke,’ he told me.

Fast-forward a quarter of a century, and the notion of universe-making – or ‘cosmogenesis’ as I dub it – seems less comical than ever. I’ve travelled the world talking to physicists who take the concept seriously, and who have even sketched out rough blueprints for how humanity might one day achieve it. Linde’s referees might have been right to be concerned, but they were asking the wrong questions. The issue is not who might be offended by cosmogenesis, but what would happen if it were truly possible. How would we handle the theological implications? What moral responsibilities would come with fallible humans taking on the role of cosmic creators?

Theoretical physicists have grappled for years with related questions as part of their considerations of how our own Universe began. In the 1980s, the cosmologist Alex Vilenkin at Tufts University in Massachusetts came up with a mechanism through which the laws of quantum mechanics could have generated an inflating universe from a state in which there was no time, no space and no matter. There’s an established principle in quantum theory that pairs of particles can spontaneously, momentarily pop out of empty space. Vilenkin took this notion a step further, arguing that quantum rules could also enable a minuscule bubble of space itself to burst into being from nothing, with the impetus to then inflate to astronomical scales. Our cosmos could thus have been burped into being by the laws of physics alone. To Vilenkin, this result put an end to the question of what came before the Big Bang: nothing. Many cosmologists have made peace with the notion of a universe without a prime mover, divine or otherwise.

At the other end of the philosophical spectrum, I met with Don Page, a physicist and evangelical Christian at the University of Alberta in Canada, noted for his early collaboration with Stephen Hawking on the nature of black holes. To Page, the salient point is that God created the Universe ex nihilo – from absolutely nothing. The kind of cosmogenesis envisioned by Linde, in contrast, would require physicists to cook up their cosmos in a highly technical laboratory, using a far more powerful cousin of the Large Hadron Collider near Geneva. It would also require a seed particle called a ‘monopole’ (which is hypothesized to exist by some models of physics, but has yet to be found).

The idea goes that if we could impart enough energy to a monopole, it will start to inflate. Rather than growing in size within our Universe, the expanding monopole would bend spacetime within the accelerator to create a tiny wormhole tunnel leading to a separate region of space. From within our lab we would see only the mouth of the wormhole; it would appear to us as a mini black hole, so small as to be utterly harmless. But if we could travel into that wormhole, we would pass through a gateway into a rapidly expanding baby universe that we had created. (A video illustrating this process provides some further details.)

We have no reason to believe that even the most advanced physics hackers could conjure a cosmos from nothing at all, Page argues. Linde’s concept of cosmogenesis, audacious as it might be, is still fundamentally technological. Page, therefore, sees little threat to his faith. On this first issue, then, cosmogenesis would not necessarily upset existing theological views.

But flipping the problem around, I started to wonder: what are the implications of humans even considering the possibility of one day making a universe that could become inhabited by intelligent life? As I discuss in my book A Big Bang in a Little Room (2017), current theory suggests that, once we have created a new universe, we would have little ability to control its evolution or the potential suffering of any of its residents. Wouldn’t that make us irresponsible and reckless deities? I posed the question to Eduardo Guendelman, a physicist at Ben Gurion University in Israel, who was one of the architects of the cosmogenesis model back in the 1980s. Today, Guendelman is engaged in research that could bring baby-universe-making within practical grasp. I was surprised to find that the moral issues did not cause him any discomfort. Guendelman likens scientists pondering their responsibility over making a baby universe to parents deciding whether or not to have children, knowing they will inevitably introduce them to a life filled with pain as well as joy.

Other physicists are more wary. Nobuyuki Sakai of Yamaguchi University in Japan, one of the theorists who proposed that a monopole could serve as the seed for a baby universe, admitted that cosmogenesis is a thorny issue that we should ‘worry’ about as a society in the future. But he absolved himself of any ethical concerns today. Although he is performing the calculations that could allow cosmogenesis, he notes that it will be decades before such an experiment might feasibly be realized. Ethical concerns can wait.

Many of the physicists I approached were reluctant to wade into such potential philosophical quandaries. So I turned to a philosopher, Anders Sandberg at the University of Oxford, who contemplates the moral implications of creating artificial sentient life in computer simulations. He argues that the proliferation of intelligent life, regardless of form, can be taken as something that has inherent value. In that case, cosmogenesis might actually be a moral obligation.

Looking back on my numerous conversations with scientists and philosophers on these issues, I’ve concluded that the editors at Nuclear Physics B did a disservice both to physics and to theology. Their little act of censorship served only to stifle an important discussion. The real danger lies in fostering an air of hostility between the two sides, leaving scientists afraid to speak honestly about the religious and ethical consequences of their work out of concerns of professional reprisal or ridicule.

We will not be creating baby universes anytime soon, but scientists in all areas of research must feel able to freely articulate the implications of their work without concern for causing offense. Cosmogenesis is an extreme example that tests the principle. Parallel ethical issues are at stake in the more near-term prospects of creating artificial intelligence or developing new kinds of weapons, for instance. As Sandberg put it, although it is understandable that scientists shy away from philosophy, afraid of being thought weird for veering beyond their comfort zone, the unwanted result is that many of them keep quiet on things that really matter.

As I was leaving Linde’s office at Stanford, after we’d spent a day riffing on the nature of God, the cosmos and baby universes, he pointed at my notes and commented ruefully: ‘If you want to have my reputation destroyed, I guess you have enough material.’ This sentiment was echoed by a number of the scientists I had met, whether they identified as atheists, agnostics, religious or none of the above. The irony was that if they felt able to share their thoughts with each other as openly as they had with me, they would know that they weren’t alone among their colleagues in pondering some of the biggest questions of our being.Aeon counter – do not remove

 

This article was originally published at Aeon and has been republished under Creative Commons.

CATEGORIZED UNDER: Space & Physics, Top Posts
MORE ABOUT: cosmology

For Funding, Scientists Turn to Unorthodox Sources

By Wudan Yan | June 14, 2017 11:47 am
science-funding

(Credit: isak55/Shutterstock)

When Donna Riordan first moved to the idyllic Orcas Island just off the coast of Washington state, she had no plans of doing any sort of research, despite her background in science and education policy. But a few years later, in 2012, she learned that Pacific International Terminals, part of marine and rail cargo operating company SSA Marine, planned to build the largest coal transport terminal in North America. She’d be able to see it from her home.

The proposed site was on top of two recently discovered fault lines. Riordan wanted to investigate the seismic hazards — which could influence how the terminal should be built, if at all. But there was one issue: how she could get the necessary money. Read More

CATEGORIZED UNDER: Living World, Top Posts
MORE ABOUT: science policy

Meet Dean Lomax, Master of the Prehistoric ‘Death March’

By Jon Tennant | June 12, 2017 12:35 pm
lomax2

Lomax meticulously studies an ammonite death march. (Courtesy: Dean Lomax)

Paleontologists study creatures that have long ceased to be, all in the hopes of “resurrecting” the history of their lives on Earth.

But paleontologist Dean Lomax, an Honorary Visiting Scientist at the University of Manchester, has made a name for himself recreating a very specific part of ancient creatures’ lives: their final struggle before death. Read More

CATEGORIZED UNDER: Living World, Top Posts
MORE ABOUT: paleontology

The Mother of All Apples Is Disappearing

By John Wenz | June 8, 2017 9:49 am
Malus-sieversii

You probably haven’t eaten this fruit before, but you may have one of its descendants in your house right now. (Credit: petrOlly/Flickr)

In the wilds of Kazakhstan, there’s an unassuming tree that bears an unassuming fruit. Like many plant species, development encroaches on its usual territory while climate change makes it harder for the tree to thrive and bear healthy yields of fruit.

You probably haven’t eaten this fruit before, but you may have one of its descendants in your house right now. After all, its children have more than 7,500 varieties in an assortment of colors and tastes and textures. Read More

CATEGORIZED UNDER: Environment, Top Posts
MORE ABOUT: plants

The 4 Big Discoveries Underpinning Our Knowledge of the Universe

By Scott Bembenek | June 7, 2017 11:53 am
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Astronomers using the Hubble Space Telescope assembled a comprehensive view of the evolving universe. (Credit: NASA/ESA)

For many, science is nothing more than that class you were required to take in school. However, whether you realize it or not, science is all around us, and it impacts every aspect of our lives. And, the stories behind key scientific discoveries, though not commonly known, are truly inspiring.

So, if you want a quick refresher on how the universe works, focus on these four fascinating discoveries and the history behind them: Read More

CATEGORIZED UNDER: Space & Physics, Top Posts
MORE ABOUT: cosmology, physics

The Dark Side of Laughter

laughter

(Credit: durantelallera/Shutterstock)

When you hear someone laugh behind you, you probably picture them on the phone or with a friend – smiling and experiencing a warm, fuzzy feeling inside. Chances are just the sound of the laughter could make you smile or even laugh along. But imagine that the person laughing is just walking around alone in the street, or sitting behind you at a funeral. Suddenly, it doesn’t seem so inviting.

The truth is that laughter isn’t always positive or healthy. According to science, it can be classified into different types, ranging from genuine and spontaneous to simulated (fake), stimulated (for example by tickling), induced (by drugs) or even pathological. But the actual neural basis of laughter is still not very well known – and what we do know about it largely comes from pathological clinical cases. Read More

CATEGORIZED UNDER: Health & Medicine, Top Posts

Malaria During Pregnancy Could Bolster Babies’ Immunity

By Kim Smuga-Otto | June 5, 2017 3:27 pm
tanzanian-mother

A mother and baby from the village of Pomerini, Tanzania. It’s estimated that the disease kills 60,000 to 80,000 people there annually. (Credit: Franco Valpato/Shutterstock)

You have a bit of your mother in you, literally.

When scientists performed biopsies of young adults’ organs, they’ve found maternal cells embedded in hearts, kidneys, and liver. This phenomenon, called microchimerism, is caused by a small number of cells passing through the placenta during pregnancy. The transfer goes both ways, and scientists think it’s like a meet-and-greet between mom and fetus, preventing their immune systems from treating each other’s cells as dangerous invaders. But that doesn’t explain why these cells stick around long after birth. Read More

CATEGORIZED UNDER: Health & Medicine, Top Posts

How the Chemicals in Sunscreen Protect Our Skin

Don’t skimp on the SPF. Sabphoto via Shutterstock.com

Don’t skimp on the SPF. (Credit: Sabphoto/Shutterstock)

Kerry Hanson, University of California, Riverside

Not so long ago, people like my Aunt Muriel thought of sunburn as a necessary evil on the way to a “good base tan.” She used to slather on the baby oil while using a large reflector to bake away. Aunt Muriel’s mantra when the inevitable burn and peel appeared: Beauty has its price. The Conversation

Was she ever right about that price – but it was a lot higher than any of us at the time recognized. What sun addicts didn’t know then was that we were setting our skin up for damage to its structural proteins and DNA. Hello, wrinkles, liver spots and cancers. No matter where your complexion falls on the Fitzpatrick Skin Type scale, ultraviolet radiation (UV) from the sun or tanning beds will damage your skin.

Today, recognition of the risks posed by UV rays has motivated scientists, myself included, to study what’s going on in our cells when they’re in the sun – and devise modern ways to ward off that damage.

UV light that affects our skin has a shorter wavelength than the parts of the electromagnetic spectrum we can see. Inductiveload, NASA, CC BY-SA

UV light that affects our skin has a shorter wavelength than the parts of the electromagnetic spectrum we can see.
(Credit: Inductiveload/NASA/CC BY-SA)

What Happens When Sun Hits Skin

Sunlight is composed of packets of energy called photons. The visible colors we can see by eye are relatively harmless to our skin; it’s the sun’s ultraviolet (UV) light photons that can cause skin damage. UV light can be broken down into two categories: UVA (in the wavelength range 320-400 nanometers) and UVB (in the wavelength range 280–320 nm).

(Credit: The Conversation, CC-BY-ND)

(Credit: The Conversation, CC-BY-ND)

Our skin contains molecules that are perfectly structured to absorb the energy of UVA and UVB photons. This puts the molecule into an energetically excited state. And as the saying goes, what goes up must come down. In order to release their acquired energy, these molecules undergo chemical reactions – and in the skin that means there are biological consequences.

Interestingly, some of these effects used to be considered helpful adaptations – though we now recognize them as forms of damage. Tanning is due to the production of extra melanin pigment induced by UVA rays. Exposure to the sun also turns on the skin’s natural antioxidant network, which deactivates highly destructive reactive oxygen species (ROS) and free radicals; if left unchecked, these can cause cellular damage and oxidative stress within the skin.

We also know that UVA light penetrates deeper into the skin than UVB, destroying a structural protein called collagen. As collagen degrades, our skin loses its elasticity and smoothness, leading to wrinkles. UVA is responsible for many of the visible signs of aging, while UVB light is considered the primary source of sunburn. Think “A” for aging and “B” for burning.

DNA itself can absorb both UVA and UVB rays, causing mutations which, if unrepaired, can lead to non-melanoma (basal cell carcinoma, squamous cell carcinoma) or melanoma skin cancers. Other skin molecules pass absorbed UV energy on to those highly reactive ROS and free radicals. The resulting oxidative stress can overload the skin’s built-in antioxidant network and cause cellular damage. ROS can react with DNA, forming mutations, and with collagen, leading to wrinkles. They can also interrupt cell signaling pathways and gene expression.

The end result of all of these photoreactions is photodamage that accumulates over the course of a lifetime from repeated exposure. And – this cannot be emphasized enough – this applies to all skin types, from Type I (like Nicole Kidman) to Type VI (like Jennifer Hudson). Regardless of how much melanin we have in our skin, we can develop UV-induced skin cancers and we will all eventually see the signs of photo-induced aging in the mirror.

Filtering Photons Before Damage Is Done

The good news, of course, is that the risk of skin cancer and the visible signs of aging can be minimized by preventing overexposure to UV radiation. When you can’t avoid the sun altogether, today’s sunscreens have got your back (and all the rest of your skin too).

Sunscreens employ UV filters: molecules specifically designed to help reduce the amount of UV rays that reach through the skin surface. A film of these molecules forms a protective barrier either absorbing (chemical filters) or reflecting (physical blockers) UV photons before they can be absorbed by our DNA and other reactive molecules deeper in the skin.

(Credit: The Conversation, CC-BY-ND)

(Credit: The Conversation, CC-BY-ND)

In the United States, the Food and Drug Administration regulates sunscreens as drugs. Because we were historically most concerned with protecting against sunburn, 14 molecules that block sunburn-inducing UVB rays are approved for use. That we have just two UVA-blocking molecules available in the United States – avobenzone, a chemical filter; and zinc oxide, a physical blocker – is a testament to our more recent understanding that UVA causes trouble, not just tans.

The FDA also has enacted strict labeling requirements – most obviously about SPF (sun protection factor). On labels since 1971, SPF represents the relative time it takes for an individual to get sunburned by UVB radiation. For example, if it takes 10 minutes typically to burn, then, if used correctly, an SPF 30 sunscreen should provide 30 times that – 300 minutes of protection before sunburn.

“Used correctly” is the key phrase. Research shows that it takes about one ounce, or basically a shot glass-sized amount of sunscreen, to cover the exposed areas of the average adult body, and a nickel-sized amount for the face and neck (more or less, depending on your body size). The majority of people apply between a quarter to a half of the recommended amounts, placing their skin at risk for sunburn and photodamage.

In addition, sunscreen efficacy decreases in the water or with sweating. To help consumers, FDA now requires sunscreens labeled “water-resistant” or “very water-resistant” to last up to 40 minutes or 80 minutes, respectively, in the water, and the American Academy of Dermatology and other medical professional groups recommend reapplication immediately after any water sports. The general rule of thumb is to reapply about every two hours and certainly after water sports or sweating

 In the U.S., the FDA regulates sunscreens available to consumers. Sheila Fitzgerald/Shutterstock.com

In the U.S., the FDA regulates sunscreens available to consumers. (Credit: Sheila Fitzgerald/Shutterstock)

What Makes A Good Sunscreen

To get high SPF values, multiple UVB UV filters are combined into a formulation based upon safety standards set by the FDA. However, the SPF doesn’t account for UVA protection. For a sunscreen to make a claim as having UVA and UVB protection and be labeled “Broad Spectrum,” it must pass FDA’s Broad Spectrum Test, where the sunscreen is hit with a large does of UVB and UVA light before its effectiveness is tested.

This pre-irradiation step was established in FDA’s 2012 sunscreen labeling rules and acknowledges something significant about UV-filters: some can be photolabile, meaning they can degrade under UV irradiation. The most famous example may be PABA. This UVB-absorbing molecule is rarely used in sunscreens today because it forms photoproducts that elicit an allergic reaction in some people.

But the Broad Spectrum Test really came into effect only once the UVA-absorbing molecule avobenzone came onto the market. Avobenzone can interact with octinoxate, a strong and widely used UVB absorber, in a way that makes avobenzone less effective against UVA photons. The UVB filter octocrylene, on the other hand, helps stabilize avobenzone so it lasts longer in its UVA-absorbing form. Additionally, you may notice on some sunscreen labels the molecule ethylhexyl methoxycrylene. It helps stabilize avobenzone even in the presence of octinoxate, and provides us with longer-lasting protection against UVA rays.

Next up in sunscreen innovation is the broadening of their mission. Because even the highest SPF sunscreens don’t block 100 percent of UV rays, the addition of antioxidants can supply a second line of protection when the skin’s natural antioxidant defenses are overloaded. Some antioxidant ingredients my colleagues and I have worked with include tocopheral acetate (Vitamin E), sodium ascorbyl phosophate (Vitamin C), and DESM. And sunscreen researchers are beginning to investigate if the absorption of other colors of light, like infrared, by skin molecules has a role to play in photodamage.

As research continues, one thing we know for certain is that protecting our DNA from UV damage, for people of every color, is synonymous with preventing skin cancers. The Skin Cancer Foundation, American Cancer Society and the American Academy of Dermatology all stress that research shows regular use of an SPF 15 or higher sunscreen prevents sunburn and reduces the risk of non-melanoma cancers by 40 percent and melanoma by 50 percent.

We can still enjoy being in the sun. Unlike my Aunt Muriel and us kids in the 1980s, we just need to use the resources available to us, from long sleeves to shade to sunscreens, in order to protect the molecules in our skin, especially our DNA, from UV damage.

 

This article was originally published on The Conversation. Read the original article.

CATEGORIZED UNDER: Health & Medicine, Top Posts
MORE ABOUT: personal health

Emerging Editing Technologies Obscure the Line Between Real and Fake

By Nathaniel Scharping | May 17, 2017 3:15 pm
Jennifer in Paradise (Credit: John Knoll)

Jennifer in Paradise (Credit: John Knoll)

The image is modest, belying the historic import of the moment. A woman on a white sand beach gazes at a distant island as waves lap at her feet — the scene is titled simply “Jennifer in Paradise.”

This picture, snapped by an Industrial Light and Magic employee named John Knoll while on vacation in 1987, would become the first image to be scanned and digitally altered. When Photoshop was introduced by Adobe Systems three years later, the visual world would never be the same. Today, prepackaged tools allow nearly anyone to make a sunset pop, trim five pounds or just put celebrity faces on animals. Read More

CATEGORIZED UNDER: Technology, Top Posts
MORE ABOUT: computers
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