Results 21 to 30 of about 103,519 (218)

Operator pencil passing through a given operator

, 2013
Let $\Delta$ be a linear differential operator acting on the space of densities of a given weight $\lo$ on a manifold $M$. One can consider a pencil of operators $\hPi(\Delta)=\{\Delta_\l\}$ passing through the operator $\Delta$ such that any $\Delta_\l$
A. Biggs, H. M. Khudaverdian, Peetre J., Peetre J.   +3 more
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Time operator in QFT with Virasoro constraints

, 2012
Time operator is studied on the basis of field quantization, where the difficulty stemming from Pauli's theorem is circumvented by borrowing ideas from the covariant quantization of the bosonic string, i.e., one can remove the negative energy states by ...
Aharonov, Atiyah, Bargmann, Bokes, Busch, Cai-Dong Xiong, Davies, Egusquiza, Fertig, Fujikawa, Galapon, Giannitrapani, Gour, Hegerfeldt, Herrmann, Hilgevoord, Kilbas, Kobe, Landauer, Muga, Muga, Olkhovsky, Olkhovsky, Olkhovsky, Olkhovsky, Olkhovsky, Olkhovsky, Pauli, Polchinski, Qi Qiu, Recami, Recami, Skulimowski, Skulimowski, Steinberg, Unruh, Wang, Wang, Wang, Yamada, Yu, Zhi-Yong Wang, Zwiebach   +42 more
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Equality Between the Spectrum of PT-Symmetric Shrödinger Operators and Their Adjoint

Mathematics
In classical spectral theory, self-adjoint differential operators satisfy the relation σ(L)=σ(L∗). However, this is not necessarily true for non-self-adjoint operators.
Ece Özdemir, Alp Arslan Kıraç
doaj   +1 more source

Self-adjoint curl operators [PDF]

Annali di Matematica Pura ed Applicata, 2011
We study the exterior derivative as a symmetric unbounded operator on square integrable 1-forms on a 3D bounded domain $D$. We aim to identify boundary conditions that render this operator self-adjoint. By the symplectic version of the Glazman-Krein-Naimark theorem this amounts to identifying complete Lagrangian subspaces of the trace space of H(curl ...
Hiptmair, Ralf, Kotiuga, P. Robert, Tordeux, Sébastien   +2 more
openaire   +5 more sources

The Huang–Yang Formula for the Low‐Density Fermi Gas: Upper Bound

Communications on Pure and Applied Mathematics, EarlyView.
ABSTRACT We study the ground state energy of a gas of spin 1/2$1/2$ fermions with repulsive short‐range interactions. We derive an upper bound that agrees, at low density ϱ$\varrho$, with the Huang–Yang conjecture. The latter captures the first three terms in an asymptotic low‐density expansion, and in particular the Huang–Yang correction term of order
Emanuela L. Giacomelli, Christian Hainzl, Phan Thành Nam, Robert Seiringer   +3 more
wiley   +1 more source

Weyl-Titchmarsh theory for Sturm-Liouville operators with distributional potentials [PDF]

Opuscula Mathematica, 2013
We systematically develop Weyl-Titchmarsh theory for singular differential operators on arbitrary intervals \((a,b) \subseteq \mathbb{R}\) associated with rather general differential expressions of the type \begin{equation*}\tau f = \frac{1}{\tau} (-(p[f'
Jonathan Eckhardt, Fritz Gesztesy, Roger Nichols, Gerald Teschl   +3 more
doaj   +1 more source

The Two-Spectra Inverse Problem for Semi-Infinite Jacobi Matrices in The Limit-Circle Case

, 2008
We present a technique for reconstructing a semi-infinite Jacobi operator in the limit circle case from the spectra of two different self-adjoint extensions.
B. Simon, B. Simon, B.M. Brown, B.M. Levitan, D. Chelkak, F. Gesztesy, F. Gesztesy, F. Gesztesy, G. Borg, G. Teschl, G. Teschl, G.Š. Guseĭnov, J.M. Berezans′kiĭ, L. Fu, L.O. Silva, L.V. Ahlfors, Luis O. Silva, M. Kreĭn, M.G. Gasymov, M.G. Gasymov, M.G. Kreĭn, M.G. Kreĭn, M.G. Kreĭn, M.L. Gorbachuk, N.I. Akhiezer, N.I. Akhiezer, R. Weikard, R.Z. Halilova, Ricardo Weder, S. Albeverio, T. Aktosun, T. Aktosun, V.A. Marčenko, W.F. Donoghue Jr.   +33 more
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Invariant Measure and Universality of the 2D Yang–Mills Langevin Dynamic

Communications on Pure and Applied Mathematics, EarlyView.
ABSTRACT We prove that the Yang–Mills (YM) measure for the trivial principal bundle over the two‐dimensional torus, with any connected, compact structure group, is invariant for the associated renormalised Langevin dynamic. Our argument relies on a combination of regularity structures, lattice gauge‐fixing and Bourgain's method for invariant measures ...
Ilya Chevyrev, Hao Shen
wiley   +1 more source

Operators on Soft Inner Product Spaces

Fuzzy Information and Engineering, 2014
In the present paper, self-adjoint operator and completely continuous operator on soft inner product spaces have been introduced and some basic properties of such operators are studied.
Sujoy Das, S.K. Samanta
doaj   +1 more source

Partially fundamentally reducible operators in Krein spaces [PDF]

, 2014
A self-adjoint operator $A$ in a Krein space $\bigl({\mathcal K},[\,\cdot\,,\cdot\,]\bigr)$ is called partially fundamentally reducible if there exist a fundamental decomposition ${\mathcal K} = {\mathcal K}_+ [\dot{+}] {\mathcal K}_-$ (which does not ...
Derkach, Vladimir, Ćurgus, Branko
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