Research over the past few years has put into question the status of the Tyrannosaurus rex as one of the top predators of the dinosaur world, suggesting that the species was actually more of a scavenger. But new analysis of a T. rex tooth embedded in the tail of a herbivorous dinosaur has confirmed that T. rex was definitely a predator to be feared.

What are the characteristics of the Solar System that lead to the origins of life?

The possibility of finding life elsewhere is for many people the most compelling reason for humankind to explore beyond the Earth.  We believe that  liquid water and carbon are required for life to arise and thrive, as well as a source of energy.  Many places in the Solar System provide these, at least for a time; not only planets, but also some moons and even certain comets.  But for life to arise we presume that a hospitable environment must be more than just transient.

The Earth is in the continuously habitable zone, meaning at our size and at our distance from the Sun water has been stable at the surface even though the brightness of the Sun has varied.  Not all planets are so lucky.  We now know that there once was liquid water on the surface of Mars, but was it there long enough for life to develop?  We are not sure, but its possible and if so then life might still linger beneath the surface, perhaps in a place where sub-surface heat meets the surface permafrost.  There are other places where there has been liquid water for as long as on Earth. Jupiter's icy moon Europa almost certainly has a liquid water ocean beneath the surface even though its five times further from the Sun than we are.  If there are hydrothermal vents at the bottom of Europa's ocean, then that would seem a very hospitable place for life, but that doesn't mean its there.  The only way we are going to find out is by going there.  Other moons that may have liquid water deep below the surface include Jupiter's moons Callisto and Ganymede as perhaps Saturn's moons Titan and Enceladus.

Giant panda Lun Lun gave birth to twins on Monday at Zoo Atlanta. To increase their chances of survival, both cubs [pictured] are being rotated between their mum and an incubator, hence receiving the best possible care.

April 15, 2013: In science fiction, finding antimatter on board your spaceship is not good news. Usually, it means you're moments away from an explosion.

In real life, though, finding antimatter could lead to a Nobel Prize.

On April 3rd, researchers led by Nobel Laureate Samuel Ting of MIT announced that the Alpha Magnetic Spectrometer, a particle detector operating onboard the International Space Station since 2011, has counted more than 400,000 positrons, the antimatter equivalent of electrons.  There’s no danger of an explosion, but the discovery is sending shock waves through the scientific community.

A new ScienceCast video explores the possibility that signs of dark matter have been detected onboard the International Space Station. Play it

"These data show the existence of a new physical phenomenon," wrote Ting and colleagues in an article published in the Physical Review Letters. "It could be a sign of dark matter."

The Alpha Magnetic Spectrometer (“AMS” for short) was delivered to the ISS by the space shuttle Endeavour on its final flight in May 2011. In its first 18 months of operations, from May 19, 2011 to December 10, 2012, the AMS analyzed 25 billion cosmic ray events. Of these, an unprecedented number were unambiguously identified as positrons.

But where do the positrons come from?  The Universe is almost completely devoid of antimatter, so the positron fraction of cosmic ray electrons--as much as 10%--is a little surprising.Cosmic rays are subatomic particles such as protons and helium nuclei accelerated to near-light speed by supernova explosions and other violent events in the cosmos. Researchers have long known that cosmic rays contain a sprinkling of antimatter.  Italy's PAMELA satellite detected high-energy positrons in 2009, and NASA's Fermi gamma-ray observatory confirmed the find two years later. 

One idea is dark matter. Astronomers know that the vast majority of the material Universe is actually made of dark matter rather than ordinary matter. They just don't know what dark matter is.  It exerts gravity, but emits no light, which makes it devilishly difficult to study.

The Alpha Magnetic Spectrometer mounted outside the International Space Station.

A leading theory holds that dark matter is made of a particle called the neutralino. Collisions between neutralinos should produce a large number of high-energy positrons, which the AMS should be able to detect with unprecedented sensitivity.

"The accuracy of our measurements is 1%, which is excellent, and we have statistics unmatched by any other spacecraft," says Ting.

"So far the evidence supports the hypothesis of dark matter. But," he cautions," it does not rule out another possibility--pulsars."

Pulsars are strongly-magnetized neutron stars formed in the aftermath of supernova explosions.  They can spin on their axes thousands of times a second, flinging particles into space with fantastic energies that accelerators on Earth can't match.  Among these particles are pairs of electrons and positrons.

AMS can distinguish between pulsars and dark matter--but not yet.  "We need more data at higher energies to decide which is the correct explanation," says Ting.  "It is only a matter of time, perhaps months or a few years."

Built by scientists from 16 countries with support from the US Dept. of Energy, the Alpha Magnetic Spectrometer will continue operating for the rest of the life of the space station ­ at least until 2020. Between now and then, the mystery of dark matter could be solved, once and for all.

The Secrets of the universe

In physics, there are some natural laws, but many scientific

theories. There are also rather interpretations, opinions and

hypotheses on which these theories are based on.

If we leave aside the theories and the various opinions and

interpretations as "man's work", then only the laws of nature

will remain. The empirically confirmed and universally valid

laws of nature do explain the relationships and

interrelationships of physical phenomena. However, there is

a problem: they contain partially natural constants that only

can be determined by measurement. While describing the

processes of nature, one will encounter physical constants,

whose values can be measured, but so far no one knows what

they are to be attributed to.

The secrets of the universe are thus hidden in the constants

of nature. Consequently, many well-known physicists had

the desire to derive the number of fundamental constants

from a single constant.

There are over a hundred fundamental constants, but only

about two dozen of them are elementary, and the rest can be

derived from them. After the discovery of the final formula I

have therefore derived the basic constants of nature,

because it is possible to explain the entire universe with

them. The derived constants of nature have been selected

after careful consideration, and as we shall see later, even

these fundamental constants of nature are based on a single

number, namely the elementary constant.

Einstein also was dissatisfied with the constants of nature,

and he has described it as follows: "... I cannot compellingly

think of any reasonable and consistent theory that

explicitly contains one number which could also have been

chosen as another number by the whim of the Creator,

where the world qualitatively would have been represented

in a different way in its laws. "

For Einstein, the most elementary constants of nature such

as the speed of light, gravitational constant and the Planck

quantum of action were not really fundamental, because

their value still depends on "conventional" units. Only if it

could be succeed to create one quantity from several

constants that is a pure numerical value without unit of

measurement, then a universal constant would exist

according to Einstein's view. However the numerical value of

this universal, absolute constant should be determined by

the logical basis of the physical theory.

The fascinating thing about the universe is its space with the immense micro- and macrocosm size. Not only in the

macrocosm between planets, solar systems and galaxies, but also in the microcosm in the atoms and its components is the

“empty space” is the decisive element. Therefore, one must first of all understand the “empty” space of which it mainly

consists in order to be able to understand the universe as a whole.

It is known that the “empty” space in fact is not empty but contains virtual particles, ominous dark matter and dark

energy.

· However, what are the empty space and thus the entire universe?

· What is energy, mass, charge? What do they consist of? 

· Why is the speed of light constant?

· Is it possible to derive the constants of nature?

· Does a Theory of everything exist?

Inter aila, we will have a look on these questions and solve some other mysteries of the universe. Thereby, new questions

and new mysteries will arise, but we will see that the universe, made up of space, time and energy is made up in an

unprecedented form.

The new world model is a theory which currently is in development, some of the results and the "final formula" hereby is

published. In this edition, I am handling the key aspects of the new model of the world. Based on equations derived from

fundamental physical constants of nature that play a central role in physics, I will demonstrate that it is possible to explain

the entire universe with a brief "final formula". With the aid of the final formula, we also will experience how time works and

how the three-dimensional space is created.

Many smart people have tried for a long time to derive all physical properties of the universe from a single formula.

However so far, all attempts have failed. It seems that the reason for this failure was the imperfection of the existing

theories. Viewing the universe from a different perspective and leaving the assigned paths of the previous theories, we at

least reach a world model with a final formula. With this book it is demonstrated how to explain the recent recognitions in

physics also from another perspective. Accordingly, modern physics is completed and enhanced. 

I have not searched for the final formula, I discovered it by chance, just like Archimedes who discovered buoyancy force in

the bathtub or Newton, who discovered the gravitational force under an apple tree. Afterwards, I made some calculations

with the final formula and have seen with a great astonishment, that the entire universe can be explained with this formula.  

Also some problems with previous theories will be highlighted in this book:

·  Newton believed that it was gravity which holds together the universe. Even today many people believe in this but no

one is able to explain what actually causes gravity. Thanks to the Final formula we are able to solve the mystery of gravity

and based on the derived gravitational constant we will be able to learn how it works.

·  Einstein could not exactly explain space and time although his famous theories were based on it. He summarized these

as “Spacetime” and assumed that the space bended itself. With the final formula we now can reveal the great secrets of

space and time.

·  Planck discovered the quantum of action and accordingly laid the foundation for quantum physics. However, his

quantized quantities do include the gravitational constant and are therefore useless, as we shall see in the appropriate

section.

But, dealing with the universe, the more clearly one recognizes the outstanding achievements of the researchers at that

times of period. They do not lose at any way authority, on the contrary, only thanks to their intellectual achievements; we

are now able to continue their scientific heritage. However, every theory becomes outdated over time through new

knowledge, and accordingly, science develops more and more.

The individual chapters and sections in this book are based on each. We will first start with the smallest dimension in the

microcosm and, in the penultimate chapter will try to describe some structures in the macrocosm. Since everything in

the universe depends on one another, it is inevitable that one can understand much better the new world

model and the final formula, after reading the whole book. Because, much more things will be more

understandable in the overall context.

Emmanuel Dunand / AFP - Getty Images

Is it reality? Magician David Blaine stands under lighting bolts at the start of his latest performance "Electrified" in New York in October 2012.

Perhaps our human senses are deceiving us — maybe existence is an illusion, and reality isn't real.

The idea that everything we know is merely a construction of our minds is investigated in the next episode of the Science Channel program "Through the Wormhole," hosted by Morgan Freeman. The episode premieres Wednesday at 10 p.m. EDT.

"What is real?" Freeman asks in the show. "How can we be certain that the universe around us actually exists? And how can we know that the world we see matches what anyone else experiences?"

Scientists design experiment to figure out what's real

Human senses are fallible. What people think they perceive is actually filtered and processed by the brain to construct a useful view of the world. Normally, this filtering is helpful, allowing people to sort out important information from the barrage of data that comes in every minute from their environment.

But this filtering ability can become a weakness, as it often does when we're watching a magician.

"A good magician will tap into universal brain processes that underlie perception," said Lawrence Rosenblum, a psychologist at the University of California, Riverside and a magician himself. For instance, a magician often directs the audience's gaze to one hand while he does something with the other.

But Rosenblum doesn't see the human tendency to fall for such misdirection as evidence that all of reality exists only in our minds. "Our perceptual system can be fooled, but I do not take that at all to mean that we're constructing reality," he told LiveScience.

All in the mindAs members of society, people create a form of collective reality. "We are all part of a community of minds," Freeman says in the show.

For example, money, in reality, consists of pieces of paper, yet those papers represent something much more valuable. The pieces of paper have the power of life and death, Freeman says — but they wouldn't be worth anything if people didn't believe in their power.

Money is fiction, but it's useful fiction.

Another fiction humans collectively engage in is optimism. Neuroscientist Tali Sharot of University College London studies "the optimism bias": people's tendency to generally overestimate the likelihood of positive events in their lives and underestimate the likelihood of negative ones.

In the show, Sharot does an experiment in which she puts a man in a brain scanner, and asks him to rate the likelihood that negative events, such as lung cancer, will happen to him. Then, he is given the true likelihood.

When the actual risks differ from the man's estimates, his frontal lobes light up. But the brain area does a better job of reacting to the discrepancy when the reality is more positive than what he guessed, Sharot said.

This shows how humans are somewhat hardwired to be optimistic. That may be because optimism "tends to have a lot of positive outcomes," Sharot told LiveScience. Optimistic people tend to live longer, healthier, more successful lives, she said, and the act of positive thinking can be a self-fulfilling prophecy. "If you think you're more likely to get promoted, you're more likely to put in more effort and work long hours," Sharot said.

But this slightly distorted view of the world can also be a weakness — a person might continue to smoke because they don't expect to get lung cancer, for example. Being more realistic is important in some cases, Sharot cautioned.

Physical realityPhysicists look beyond the human mind for external reality, but even that reality isn't absolute truth. Fundamental reality as scientists understand it is based on quantum mechanics, a realm where all manner of strange things occur. An electron can behave as either a particle or a wave, depending on how one measures it. And scientists can measure either a particle's position or its momentum at any given time, but never both.

"Quantum mechanics is simply the best theory we've ever developed," theoretical physicist David Tong of Cambridge University says in the show. But so much of this reality is by definition unknowable. Another physicist featured in the show, Steven Nahn of MIT, says "I absolutely believe reality is a real thing, but that does not mean we understand it." Nahn was part of the team of scientists who found evidence in 2012 for the Higgs boson, the particle that gives other particles their mass.

The universe may turn out to have more dimensions than we know about, where fundamental forces behave very differently than how we perceive them. For example, gravity is the weakest of the four fundamental forces, but in other dimensions, it could be just as strong. "Things would be very different in this hidden reality," Freeman says. 

The universe could even be a kind of hologram. The amount of information that can be stored in a region of space is proportional to the region's surface area, rather than its volume – a property known as the holographic principle. One possible implication is that reality is actually two-dimensional, and the three-dimensional world is merely an illusion, which would explain some of the wackiness of quantum mechanics.

All of these views of the world — those that we perceive in our minds, and those that physicists discover in the universe — are flavors of reality. What humans perceive as reality may be no more than an illusion. But in the end, maybe that doesn't matter.