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Observabel dari \f{topological defect} di alam semesta dapat diperlajari dengan menyelidiki ruang-waktunya. Konsekuensi paling jelas dari ruang-waktu untuk pendeteksi objek tersebut adalah pelensaan gravitasi. Salah satu dari tipe \f{topological defect} yang paling mungkin untuk ada adalah dawai kosmik. Tensi/tegangan dalam dawai dapat disetimbangkan dengan adanya arus mengalir di dalamnya, memungkinkan terbentuknya \f{loop} stabil yang dinamakan vorton. Keberadaan objek-objek ini diprediksi dalam model terra Witten $U(1)\times U(1)$ dan teori elektrolemah $SU(2)\times U(1)$. Dalam studi ini, ruang-waktu dari \f{loop} dawai kosmik superkonduktor ditelaah, dimulai dari solusi metrik dari vorton \f{chiral} lingkaran, efek pelensaan gravitasinya, dan gambar terlensakan dari beberapa keluarga solusi vorton \f{chiral} menggunakan pendekatan lensa tipis. Kita juga menganalisis dinamika dari \f{loop} dawai superkonduktor dalam latar ruang-waktu Kerr-Newman.

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Observables of topological defects in the universe can be studied by examining its spacetime. The most obvious properties of spacetime for the detection of such objects would be the gravitational lensing. One of the likely type of topological defect to exist is the cosmic string. The tension of the string could be balanced by a current flowing inside it, possibly forming a stable loop called vorton. The existence of these objects is predicted both in the Witten gauge $U(1)\times U(1)$ model and electroweak $SU(2)\times U(1)$ theory. In this study, the spacetime of superconducting string loop is examined, starting from the metric solution of a circular chiral vorton, its gravitational lensing effect, and the lensing image of various families of chiral vorton solutions using the thin lens approximation. We also analyze the dynamics of superconducting string loop in the Kerr-Newman spacetime background.

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Pelensaan gravitasi (GL), sebuah aspek integral dari relativitas umum, sangat memengaruhi pemahaman kita model lubang hitam (BH). Singularitas terpusat akibat keruntuhan gravitasi merupakan hal yang fundamental karakteristik BH Meskipun demikian, eksploitasi elektrodinamika non-linier (NLED) mengungkapkan hal tersebut konsep tegas tentang non-singularitas. Kami terutama memfokuskan analisis kami pada penghitungan sudut defleksi dalam perkiraan medan lemah dan kuat, dengan sengaja mengecualikan konfigurasi ruangwaktu asli. Biasanya, kami menghubungkan geometri efektif foton ke NLED. Sebaliknya, foton bergerak melalui jalur efektif null geodesik yang sejajar dengan geometri metrik biasa. Hasilnya menunjukkan bahwa pada medan lemah, terdapat suku tambahan pada sudut defleksi dibandingkan dengan metrik Reissner-Nordstrom (RN). Jika dibandingkan dengan BH biasa, gambar tersier bergeser ke lokasi yang berbeda. Dalam medan kuat, sudut defleksi bertambah terhadap muatan listrik. Studi ini memberikan gambaran singkat mengenai temuan-temuan ini, mengkontekstualisasikannya dalam wacana rumit seputar singularitas dan GL BH.

 

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Gravitational lensing, an integral aspect of general relativity, profoundly impacts our understanding of black hole (B.H.) models. A centered singularity resulting from gravitational collapse is a fundamental characteristic of a B.H. Nonetheless, the exploitation of non-linear electrodynamics (NLED) divulges the emphatic concept of non-singularity. We primarily focus our analysis on calculating the deflection angle in the weak and strong field approximations, deliberately excluding the original spacetime configuration. Typically, we link the photon’s effective geometry to NLED. Instead, a photon travels through an effective null geodesic that aligns with the geometry of a regular metric. The results show that in weak fields, there is an extra term in the deflection angle compared to the Reissner-Nordstrom (R.N.) metric. When compared to a regular B.H., the tertiary image shifts to a distinct location. In a strong field, the deflection angle increases with respect to the electric charge. This study provides a concise overview of these findings, contextualizing them within the intricate discourse surrounding B.H.’s singularity and GL

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