Second Order Corrections to QED Coupling at Low Temperature

We calculate the second order corrections to vacuum polarization tensor of photons at low temperatures, i.e; T $\le 10^{10}$ K ($T << m_e$). The thermal contributions to the QED coupling constant are evaluated at temperatures below the electron mass that is $T< m_e$ . Renormalization of QED at these temperatures has explicitly been checked. The electromagnetic properties of such a thermal medium are modified. Parameters like electric permittivity and magnetic permeability of such a medium are no more constant and become functions of temperature.Comment: 8 latex pages and 1 figure (to appear in IJMP

Second Order Corrections to the Magnetic Moment of Electron at Finite Temperature

Magnetic moment of electron at finite temperature is directly related to the modified electron mass in the background heat bath. Magnetic moment of electron gets modified when it couples with the magnetic field at finite temperature through its temperature dependent physical mass. We show that the magnetic moment of electron becomes a complicated function of temperature and even change its temperature dependent behavior around the energies for primordial nucleosynthesis. We calculate the self-mass induced thermal contributions to the magnetic moment of electron, up to the two loop level, for temperatures valid around the era of primordial nucleosynthesis. A comparison of thermal behavior of the magnetic moment is also quantitatively studied in detail, around the temperatures below and above nucleosynthesis temperature range

Second Order Thermal Corrections to Electron Wavefunction

Second order perturbative corrections to electron wavefunction are calculated here at generalized temperature, for the first time. This calculation is important to prove the renormalizeability of QED through order by order cancellation of singularities at higher order. This renormalized wavefunction could be used to calculate the particle processes in the extremely hot systems such as the very early universe and the stellar cores. We have to re-write the second order thermal correction to electron mass in a convenient way to be able to calculate the wavefunction renormalization constant. A procedure for integrations of hot loop momenta before the cold loop momenta integration is maintained throughout to be able to remove hot singularities in an appropriate way. Our results, not only includes the intermediate temperatures T m (where m is the electron mass), the limits of high temperature T>>m and low temperature T<<m are also retrievable. A comparison is also done with the existing results.Comment: 12 Pages and 1 figure; Submitted for publicatio

Sweet's syndrome as a dermatological manifestation of underlying coronary artery disease

SummaryWe report an unusual case of a 50-year-old female with no significant past medical history who reported with a sudden eruption of painful erythematous papules accompanied by fever. Clinical and pathological findings were consistent with acute febrile neutrophilic dermatosis (or Sweet's syndrome). Two weeks later, she complained of chest pain and was diagnosed with non-ST elevation myocardial infarction. Coronary angiogram demonstrated stenosis of right coronary artery and left Circumflex artery. Subsequent workup to identify underlying malignant or autoimmune disorders was negative. She refused to undergo percutaneous coronary intervention and was treated conservatively with steroids, resulting in dramatic resolution of skin lesions. Six months later, the patient was readmitted with similar complaints including fever, generalized rash, and chest pain. Electrocardiography demonstrated old infero-lateral wall infarction. Cardiac enzymes were not elevated. Repeat workup failed to identify underlying systemic disorder except coronary artery disease (CAD). She recovered following administration of steroids and continued to receive medical therapy for CAD. This case demonstrates an unusual association between Sweet's syndrome and CAD in an adult female. Sweet's syndrome is considered to be a reactive phenomenon of underlying systemic disorders. Therefore, patients presenting with Sweet's syndrome should be evaluated for CAD, especially in the absence of underlying malignant or autoimmune disorders

Two Loop Low Temperature Corrections to Electron Self Energy

We recalculate the two loop corrections in the background heat bath using real time formalism. The procedure of the integrations of loop momenta with dependence on finite temperature before the momenta without it, has been followed. We determine the mass and wavefunction renormalization constants in the low temperature limit of QED, for the first time with this preferred order of integrations. The correction to electron mass and spinors in this limit is important in the early universe at the time of primordial nucleosynthesis as well as in astrophysics.Comment: 8 pages and 1 figure to appear in Chinese Physics

Memory Threads: Organizing Digital Memories to Organize Social P2P Networks

Human remember their memories based on some reference which helps in recalling those memories. These references are usually common for many people, objects, places and so on. We organize human digital memories in the form of memory threads, according to the references of the memories in order to present information about different places, persons, etc. We organize peers in our Entity-based social peer-to-peer network according to memory threads in the form of memory threads-based communities. In our approach, peers having human digital memories with similar reference keys are grouped together under certain criteria. The criteria for thread selects peers with similar digital memories and arrange them in a specific order that define a structure of thread, which allows tracing via memories and accessing peers at different locations in threads easily. This approach is more scalable because it brings the most similar peer together in a community of similar peer. The known location of peer and data allows fast data searching. Also, a community presents useful information about the entity in network