2,261 research outputs found
Japan's Orphan Tsunami of 1700: A Jello Stratigraphy Activity for K-12 Students
As a Morehead Planetarium and Science Center Science Ambassador, I created an activity for middle school science students regarding Tsunamis. I presented a brief introduction to tsunamis and how they occur, and the story of Japan's "Orphan Tsunami' in 1700. Researchers scoured coastal wetlands in the Pacific NW looking for evidence of large tsunamis. They discovered tsunami deposits in several locations that dated back to around 1700. My activity involved making Jello stratigraphy layers in opaque cups, that included tsunami sand (sprinkles) and fossils (shell shaped pasta). Students used straws to take core samples of their "wetland sediment layers) and looked for tsunami sand. Spoons were included so the students could dig trenches in their sediment layers
Development and psychometric properties of the Multidimensional Schizotypy Scale: a new measure for assessing positive, negative, and disorganized schizotypy
This dissertation reports on the development of a new self-report questionnaire measure of schizotypy â the Multidimensional Schizotypy Scale (MSS). Schizotypy offers a useful and unifying construct for understanding schizophrenia-spectrum psychopathology. Questionnaire measures have been widely used to assess schizotypy and have greatly informed our understanding of the construct; however, available measures suffer from a number of limitations, including lack of a clear conceptual framework, outdated wording, unclear factor structure, and psychometric shortcomings. The MSS is based on current conceptual models and taps positive, negative, and disorganized conceptual dimensions of schizotypy. The derivation sample included 6,265 participants sampled from four universities and Amazon Mechanical Turk. A separate cross-validation sample of 1,000 participants from these sources was used to examine the psychometric properties of the final subscales. Scale development employed classical test theory, item response theory, and differential item function methods. The positive schizotypy and negative schizotypy subscales contain 26 items each, and the disorganized schizotypy subscale contains 25 items. The psychometric properties were almost identical in the derivation and validation samples. All three subscales demonstrated good to excellent reliability, high item-scale correlations, and good item and test curve characteristics
"The daily grunt": middle class bias and vested interests in the 'Getting in Early' and 'Why Can't They Read?' reports.
It is a long-standing and commonly held belief in the UK and elsewhere that the use of elite forms of language reflects superior intellect and education. Expert opinion from sociolinguistics, however, contends that such a view is the result of middle-class bias and cannot be scientifically justified. In the 1960s and 1970s,such luminaries as Labov (1969) and Trudgill (1975) were at pains to point out to educationalists, with some success, that this 'deficit 'view of working-class children's communicative competence is not a helpful one. However, a close reading of recent think-tank reports and policy papers on language and literacy teaching in schools reveals that the linguistic deficit hypothesis has resurfaced and is likely to influence present-day educational policy and practice. In this paper I examine in detail the findings, claims and recommendations of the reports and I argue that they are biased, poorly researched and reflect the vested interests of certain specialist groups, such as speech and language therapists and companies who sell literacy materials to schools. I further argue that we need to, once again, inject the debate with the social dimensions of educational failure, and we need to move away from the pathologisation of working-class children's language patterns
Magnetic Monopoles, Electric Neutrality and the Static Maxwell-Dirac Equations
We study the full Maxwell-Dirac equations: Dirac field with minimally coupled
electromagnetic field and Maxwell field with Dirac current as source. Our
particular interest is the static case in which the Dirac current is purely
time-like -- the "electron" is at rest in some Lorentz frame. In this case we
prove two theorems under rather general assumptions. Firstly, that if the
system is also stationary (time independent in some gauge) then the system as a
whole must have vanishing total charge, i.e. it must be electrically neutral.
In fact, the theorem only requires that the system be {\em asymptotically}
stationary and static. Secondly, we show, in the axially symmetric case, that
if there are external Coulomb fields then these must necessarily be
magnetically charged -- all Coulomb external sources are electrically charged
magnetic monopoles
Mutually-Antagonistic Interactions in Baseball Networks
We formulate the head-to-head matchups between Major League Baseball pitchers
and batters from 1954 to 2008 as a bipartite network of mutually-antagonistic
interactions. We consider both the full network and single-season networks,
which exhibit interesting structural changes over time. We find interesting
structure in the network and examine their sensitivity to baseball's rule
changes. We then study a biased random walk on the matchup networks as a simple
and transparent way to compare the performance of players who competed under
different conditions and to include information about which particular players
a given player has faced. We find that a player's position in the network does
not correlate with his success in the random walker ranking but instead has a
substantial effect on its sensitivity to changes in his own aggregate
performance.Comment: A few clarifications added 14 pages, 2 tables, 6 figures. Submitte
Electron-deuteron scattering in a current-conserving description of relativistic bound states: formalism and impulse approximation calculations
The electromagnetic interactions of a relativistic two-body bound state are
formulated in three dimensions using an equal-time (ET) formalism. This
involves a systematic reduction of four-dimensional dynamics to a
three-dimensional form by integrating out the time components of relative
momenta. A conserved electromagnetic current is developed for the ET formalism.
It is shown that consistent truncations of the electromagnetic current and the
interaction kernel may be made, order-by-order in the coupling constants,
such that appropriate Ward-Takahashi identities are satisfied. A meson-exchange
model of the interaction is used to calculate deuteron vertex functions.
Calculations of electromagnetic form factors for elastic scattering of
electrons by deuterium are performed using an impulse-approximation current.
Negative-energy components of the deuteron's vertex function and retardation
effects in the meson-exchange interaction are found to have only minor effects
on the deuteron form factors.Comment: 42 pages, RevTe
Kurt Symanzik - a stable fixed point beyond triviality
In 1970 Kurt Symanzik proposed a "precarious" phi**4-theory with a negative
quartic coupling constant as a valid candidate for an asymptotically free
theory of strong interactions. Symanzik's deep insight in the non-trivial
properties of this theory has been overruled since then by the Hermitian
intuition of generations of scientists, who considered or consider this
actually non-Hermitian highly important theory to be unstable. This short -
certainly controversial - communication tries to shed some light on the
historical and formalistic context of Symanzik's theory in order to sharpen our
(quantum) intuition about non-perturbative theoretical physics between
(non)triviality and asymptotic freedom.Comment: 6 pages, no figures, new style files, revised for typos, improved
discussion, new references adde
New Approach to GUTs
We introduce a new string-inspired approach to the subject of grand
unification which allows the GUT scale to be small, \lesssim 200 TeV, so that
it is within the reach of {\em conceivable} laboratory accelerated colliding
beam devices. The key ingredient is a novel use of the heterotic string
symmetry group physics ideas to render baryon number violating effects small
enough to have escaped detection to date. This part of the approach involves
new unknown parameters to be tested experimentally. A possible hint at the
existence of these new parameters may already exist in the EW precision data
comparisons with the SM expectations.Comment: 8 pages; improved text and references, note added; extended text, 1
figure added; extended text for publication in Eur. Phys. Journal
Emergent Electroweak Symmetry Breaking with Composite W, Z Bosons
We present a model of electroweak symmetry breaking in a warped extra
dimension where electroweak symmetry is broken at the UV (or Planck) scale. An
underlying conformal symmetry is broken at the IR (or TeV) scale generating
masses for the electroweak gauge bosons without invoking a Higgs mechanism. By
the AdS/CFT correspondence the W,Z bosons are identified as composite states of
a strongly-coupled gauge theory, suggesting that electroweak symmetry breaking
is an emergent phenomenon at the IR scale. The model satisfies electroweak
precision tests with reasonable fits to the S and T parameter. In particular
the T parameter is sufficiently suppressed since the model naturally admits a
custodial SU(2) symmetry. The composite nature of the W,Z-bosons provide a
novel possibility of unitarizing WW scattering via form factor suppression.
Constraints from LEP and the Tevatron as well as discovery opportunities at the
LHC are discussed for these composite electroweak gauge bosons.Comment: 39 pages, 4 figure
Physics Beyond the Standard Model
I briefly summarize the prospects for extending our understanding of physics
beyond the standard model within the next five years.Comment: 9 pages, 2 figures, LaTeX. Presented at the 1999 UK Phenomenology
Workshop, Durham, September 1999. To be published in Journal of Physics
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