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Books > Science & Mathematics > Physics > Relativity physics
The chapters in this monograph are contributions from the Advances
in Quantum Monte Carlo symposium held at Pacifichem 2010,
International Chemical Congress of Pacific Basin Societies. The
symposium was dedicated to celebrate the career of James B.
Anderson, a notable researcher in the field. Quantum Monte Carlo
provides an ab initio solution to the Schroedinger equation by
performing a random walk through configuration space in imaginary
time. Benchmark calculations suggest that its most commonly-used
variant, "fixed-node" diffusion Monte Carlo, estimates energies
with an accuracy comparable to that of high-level coupled-cluster
calculations. These two methods, each having advantages and
disadvantages, are complementary "gold-standards" of quantum
chemistry. There are challenges facing researchers in the field,
several of which are addressed in the chapters in this monograph.
These include improving the accuracy and precision of quantum Monte
Carlo calculations; understanding the exchange nodes and utilizing
the simulated electron distribution; extending the method to large
and/or experimentally-challenging systems; and developing hybrid
molecular mechanics/dynamics and Monte Carlo algorithms.
Advances in Quantum Monte Carlo confronts the challenges in quantum
mechanics that have become progressively more prevalent in the last
five years. This book will cover the needed advances in Quantum
Monte Carlo methods including improvements and a complete range of
applications. Advances in Quantum Monte Carlo will also include a
complete spectrum of applications.
Monte Carlo methods are a class of computational algorithms for
simulating the behavior of a wide range of various physical and
mathematical systems (with many variables). Their utility has
increased with general availability of fast computers, and new
applications are continually forthcoming. The basic concepts of
Monte Carlo are both simple and straightforward and rooted in
statistics and probability theory, their defining characteristic
being that the methodology relies on random or pseudo-random
sequences of numbers. It is a technique of numerical analysis based
on the approximate solution of a problem using repeated sampling
experiments and observing the proportion of times a given property
is satisfied.
The term Monte Carlo was first used to describe calculational
methods based on chance in the 1940s, but the methods themselves
preceded the term by as much as a century. Quantum Monte Carlo
(QMC) first appeared in 1982 and similarly was preceded by
development of the related calculational methodology. The success
of QMC methods over the past few decades has been remarkable, and
this book will clearly demonstrate that success in its discussion
of applications. For isolated molecules, the basic material of
chemistry, QMC methods have produced exact solutions of the
Schroedinger equation for very small systems and the most accurate
solutions available for very large systems. The range of
applications is impressive: folding of protein molecules,
interactions in liquids, structure modeling in crystals and
enzymes, quantum dots, designing heat shields and aerodynamic
forms, architecture, design, business and economics, and even
cinema and video games (3D modeling).
This booktakes a similar approach to Henry Schaefers classic book
Quantum Chemistry (OUP, 1984 now a Dover edition), collecting
summaries of some of the most important papers in the quantum Monte
Carlo literature, tying everything together with analysis and
discussion of applications. Quantum Monte Carlo is a reference book
for quantum Monte Carlo applications, belonging near the desk of
every quantum chemist, physicist, and a wide range of scientists
and engineers across many disciplines, destined to become a
classic.
Instant Physics pulls together all the pivotal physics knowledge
and thought into one concise volume. Each page contains a discrete
'cheat sheet', which tells you the most important facts in
bite-sized chunks, meaning you can become an expert in an instant.
From black holes to black body radiation, telescopes to
microscopes, quantum mechanics to general relativity, every key
figure, discovery or idea is explained with succinct and lively
text and graphics. Perfect for the knowledge hungry and time poor,
this collection of graphic-led lessons makes psychology interesting
and accessible. Everything you need to know is here.
Somewhere near the heart of existence, shimmers the ethereal beauty
of the mystery of Time. Though seemingly familiar to us all, time
harbours secrets that penetrate the very deepest levels of reality,
and though we feel certain in our conviction that we're swept forth
upon the crest of its never-ending flow, with Einstein's discovery
of relativity came what is perhaps the most stunning realisation in
the entire history of scientific thought - the wondrously
breathtaking revelation that in reality, there's actually no such
thing as the passage of time... How can this extraordinary truth be
reconciled with the reality we so surely suppose to experience?
What does it mean for the very human concerns of life and death,
free will, identity, and self? What should it mean for our
philosophy? And how should it inform our world view? The search for
answers leads through the fantastical realm of quantum physics, and
the strange parallel worlds it describes, as we discover that the
answers which such questions provoke, are perhaps even more
profound than the questions themselves. Buried deep within the
riddle of time, lies the staggering beauty of the world. As we peel
back the layers to try and sneak a glimpse into eternity, we find a
light shining not only upon the nature of reality, but on the
nature of ourselves...
This article is dedicated to Claudio Bunster on the occasion of his
60th birthday. It is a great honor to take this opportunity to
express my gratitude to him, who in my opinion has been the
greatest national physicist ever, for his wise guidance and
intrepid support through the years. As a Chilean, I can further
tell that Claudio's contributions have been well far beyond
theoretical physics, helping our country to be ready to face future
challenges through science. Gravity in diverse dimensions is a
subject in which Claudio has done major c- tributions, encouraging
in many ways the following work, that is being made along different
fronts in collaboration with my colleagues Diego Correa, Gustavo
Dotti, Julio Oliva and David Tempo.
Thepursuitforwormholesolutions,whicharehandlesinthespacetimetopology,
it is as old as General Relativity and it has appeared in
theoretical physics within different subjects, ranging from the
attempt of describing physics as pure geometry, as in the
Einstein-Rosen bridge model of a particle [1], to the concept of
"charge withoutcharge"[2],aswell asindifferentissuesconcerningthe
Euclideanapproach to quantum gravity (see, e.g., [3]). More
recently, the systematic study of this kind of objects was pushed
forward by the works of Morris, Thorne and Yurtsever [4,5].
A short important work by Hendrik Antoon Lorentz, Dutch physicist
and Nobel Prize winner.
This book contains selected papers from the First International
Conference on the Ontology of Spacetime. Its fourteen chapters
address two main questions: first, what is the current status of
the substantivalism/relationalism debate, and second, what about
the prospects of presentism and becoming within present-day physics
and its philosophy? The overall tenor of the four chapters of the
book's first part is that the prospects of spacetime
substantivalism are bleak, although different possible positions
remain with respect to the ontological status of spacetime. Part II
and Part III of the book are devoted to presentism, eternalism, and
becoming, from two different perspectives. In the six chapters of
Part II it is argued, in different ways, that relativity theory
does not have essential consequences for these issues. It certainly
is true that the structure of time is different, according to
relativity theory, from the one in classical theory. But that does
not mean that a decision is forced between presentism and
eternalism, or that becoming has proved to be an impossible
concept. It may even be asked whether presentism and eternalism
really offer different ontological perspectives at all. The writers
of the last four chapters, in Part III, disagree. They argue that
relativity theory is incompatible with becoming and presentism.
Several of them come up with proposals to go beyond relativity, in
order to restore the prospects of presentism.
- Space and time in present-day physics and philosophy
- Introduction from scratch of the debates surrounding time
- Broad spectrum of approaches, coherently represented
This book reports on the extraordinary observation of TeV gamma
rays from the Crab Pulsar, the most energetic light ever detected
from this type of object. It presents detailed information on the
painstaking analysis of the unprecedentedly large dataset from the
MAGIC telescopes, and comprehensively discusses the implications of
pulsed TeV gamma rays for state-of-the-art pulsar emission models.
Using these results, the book subsequently explores new testing
methodologies for Lorentz Invariance Violation, in terms of a
wavelength-dependent speed of light. The book also covers an
updated search for Very-High-Energy (VHE), >100 GeV, emissions
from millisecond pulsars using the Large Area Telescope on board
the Fermi satellite, as well as a study on the promising Pulsar
Wind Nebula candidate PSR J0631. The observation of VHE gamma rays
is essential to studying the non-thermal sources of radiation in
our Universe. Rotating neutron stars, also known as pulsars, are an
extreme source class known to emit VHE gamma rays. However, to date
only two pulsars have been detected with emissions above 100 GeV,
and our understanding of their emission mechanism is still lacking.
Modern physics has forever changed the way we view and understand
physical reality. With a wide spectrum of theories, from general
relativity to quantum mechanics, our conceptions of the very big
and the very small are no longer intuitively obvious. Many
philosophers, even scientists have expressed the opinion that the
counterintuitive conclusions posited in modern physics are best
understood using spiritual terminology. In the 11 lectures in this
volume, Harav Ginsburgh, one of our generation's foremost scholars,
innovators, and teachers of Kabbalah, reveals how modern physics
reflects foundational concepts in the Torah's inner dimension. A
wide range of topics from relativity (special and general), quantum
mechanics, and string theory are addressed. Elegantly and
gracefully, Harav Ginsburgh's exposition of the topics switches
back and forth between the scientific and Torah perspectives. With
his deep insight, Harav Ginsburgh gives even well-known physical
concepts a refreshing and new treatment. Apart from carefully
drawing parallels and correspondences between the Torah's inner
dimension and modern physics, in these lectures, Harav Ginsburgh
proposes new directions for scientific research into important
areas such as a unified field theory, CPT symmetry, the
relationship between acceleration and gravitation, and the
possibility of uncovering additional dimensions in physical
reality, demonstrating how the Torah's depth can be used to
fertilize science and further our understanding of nature.
Harav Yitzchak Ginsburgh is one of our generation s foremost
expositors of Kabbalah and Chassidut and is the author of over 100
books in Hebrew, English, French, Russian, and Spanish. The
interface between Torah and science is one of the areas in which he
is known for his breakthrough work, forging a path in
revolutionizing the way we think about the relationship between
Judaism and modern science. He is also the founder and dean of the
Ba al Shem Tov School of Jewish Psychology, and his unique approach
to mathematics in Torah is now the basis of a new math curriculum
for Jewish schools.
Despite the success of general relativity in explaining classical
gravitational phenomena, several problems at the interface between
gravitation and high energy physics still remain open. The purpose
of this thesis is to explore quantum gravity and its
phenomenological consequences for dark matter, gravitational waves
and inflation. A new formalism to classify gravitational theories
based on their degrees of freedom is introduced and, in light of
this classification, it is argued that dark matter is no different
from modified gravity. Gravitational waves are shown to be damped
due to quantum degrees of freedom. The consequences for
gravitational wave events are also discussed. The non-minimal
coupling of the Higgs boson to gravity is studied in connection
with Starobinsky inflation and its implications for the vacuum
instability problem is analyzed.
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