Scott Douglas Jacobsen (Email: scott.jacobsen2025@gmail.com)

Publisher, In-Sight Publishing

Fort Langley, British Columbia, Canada

Received: October 25, 2025
Accepted: December 15, 2025
Published: December 15, 2025

Abstract

This interview with Professor İzzet Sakallı (Eastern Mediterranean University) explores how quantum cosmology and black hole physics have become practical testing grounds for ideas that sit between quantum mechanics and general relativity. Sakallı traces his entry into the field through Hawking radiation and the black hole information paradox, framing quantum gravity not as a purely aesthetic unification project but as a set of hypotheses that may leave measurable “fingerprints” in astrophysical data. He argues that the proliferation of modified-gravity models has created a methodological bottleneck: without shared benchmarks—waveform libraries for gravitational-wave comparisons, explicit uncertainty budgets, cross-theory test protocols, and strong null tests—claims about “new gravity” risk remaining irreproducible or non-decisive. The conversation then turns to concrete quantum-gravity-motivated effects, including Generalized Uncertainty Principle corrections to Hawking emission and the prospects of quasinormal-mode spectroscopy for probing (or falsifying) universal area quantization across backgrounds beyond general relativity. Throughout, Sakallı emphasizes a research posture that is simultaneously ambitious and disciplined: collaborate with observers, publish code, quantify errors, and treat speculation as speculation until nature signs the receipt—ideally via multi-messenger astronomy and the next generation of gravitational-wave detectors and telescopes.

Keywords

Area quantization, Black hole thermodynamics, Cross-paper comparability, Generalized Uncertainty Principle, Gravitational-wave detectors, Modified gravity, Multi-messenger astronomy, Null tests, Observational astronomy, Quantum cosmology, Quantum corrections, Quantum gravity, Quasinormal-mode spectroscopy, Reproducibility standards, Waveform libraries

Introduction

Professor İzzet Sakallı is a theoretical physicist at Eastern Mediterranean University whose work moves across the fault line where our two best physical frameworks—quantum mechanics and general relativity—refuse to seamlessly merge. With a publication record spanning black hole thermodynamics, quantum-gravity-inspired corrections, and modified gravity models, Sakallı operates in a research ecosystem that is simultaneously fertile and unruly: fertile because new observational instruments now watch black holes “in action,” and unruly because theoretical cosmology has produced an enormous menu of exotic alternatives to Einsteinian gravity, many of them difficult to test cleanly.

In this interview, Sakallı describes how Hawking’s discovery that black holes radiate pushed him toward quantum cosmology by turning a philosophical tension into a technical crisis: if black holes evaporate, what becomes of information? That question, for him, crystallizes the deeper incompatibility between quantum theory’s usual assumption of a fixed spacetime background and relativity’s insistence that spacetime is dynamical and responsive. He presents black holes as the universe’s most unforgiving laboratories—objects where extreme gravity may amplify otherwise invisible quantum effects, at least in principle.

Rather than treating quantum gravity as forever beyond experiment, Sakallı argues for an explicitly observational attitude: build theories that can be compared against gravitational-wave ringdowns, black hole shadow measurements, X-ray timing, and cosmological constraints, and do so with transparent error accounting. He also offers pragmatic guidance to students—master geometry, quantum theory, thermodynamics, and computation—and he insists that the field’s credibility now depends as much on shared standards and reproducibility as on ingenuity.

Main Text (Interview)

Title: Quantum Cosmology at the Frontiers of Observation: An Interview with Prof. Dr. İzzet Sakallı (1)

Interviewer: Scott Douglas Jacobsen

Interviewees: İzzet Sakallı

Professor İzzet Sakallı is a theoretical physicist at Eastern Mediterranean University whose research bridges quantum mechanics, general relativity, and observational astronomy. With over 180 publications exploring black hole thermodynamics, modified gravity theories, and quantum corrections to spacetime, his work sits at the exciting frontier where abstract mathematics meets observable reality. In this interview, he discusses the challenges of testing exotic gravity theories, the quest to observe quantum effects in astrophysical systems, and what the next generation of telescopes and gravitational wave detectors might reveal about the quantum nature of spacetime. 

Scott Douglas Jacobsen: How did you initially become interested in quantum cosmology? 

Prof. İzzet Sakallı: My journey into quantum cosmology began with a deep fascination for the paradoxes that emerge when quantum mechanics meets gravity. During my graduate studies, I encountered Stephen Hawking’s remarkable discovery that black holes aren’t truly black—they emit radiation due to quantum effects near their horizons. This revelation struck me as profoundly beautiful and troubling in equal measure. Beautiful because it connected thermodynamics, quantum field theory, and gravity in an unexpected way. Troubling because it raised the information paradox: if black holes evaporate completely, where does the information about everything they swallowed go? 

This puzzle captivated me because it sits at the boundary of our understanding. We have two extraordinarily successful theories—quantum mechanics describing the microscopic world, and general relativity describing gravity and spacetime—yet they seem fundamentally incompatible. Quantum mechanics operates on a fixed stage of spacetime, while general relativity tells us that spacetime itself is dynamic, curved by matter and energy. Reconciling these worldviews isn’t just an academic exercise; it’s essential for understanding the universe’s earliest moments after the Big Bang and what happens at the center of black holes. 

What drew me specifically to this field was the realization that we might actually test these ideas. Unlike some areas of theoretical physics that seem forever beyond experimental reach, quantum gravity leaves potential fingerprints in astrophysical observations. The incredible masses and strong gravitational fields of black holes, combined with quantum effects, create natural laboratories for exploring this physics. Working under Professor Mustafa Halilsoy, I learned to appreciate how exact solutions in modified gravity theories could bridge the gap between pure mathematics and physical reality. 

Jacobsen: What is your advice for prospective students of quantum cosmology? 

Sakalli: For students aspiring to contribute to quantum cosmology, I emphasize that this field demands both breadth and depth. You need to become fluent in multiple languages: the geometric language of general relativity, the probabilistic language of quantum mechanics, and increasingly, the computational language of modern astrophysics. 

Start with a rock-solid foundation in differential geometry and tensor calculus—these are the tools for understanding how spacetime curves and how matter moves through it. But don’t just manipulate symbols; develop physical intuition. Work through problems in classical mechanics until you can see the symmetries and conservation laws. Study thermodynamics thoroughly, because black hole thermodynamics beautifully parallels ordinary thermal physics, and recognizing these patterns will guide your understanding. 

Equally important is developing computational expertise. Modern research requires numerical methods because most interesting problems in modified gravity cannot be solved with pencil and paper alone. Learn symbolic computation packages like Mathematica, and master numerical techniques in Python or C++. The ability to solve differential equations numerically, simulate gravitational wave signals, or analyze telescope data is increasingly essential. 

However, I encourage students to maintain an interdisciplinary perspective. Quantum cosmology doesn’t exist in isolation—it connects to high-energy particle physics, observational astronomy, and mathematical physics. Read broadly. Understand the constraints from gravitational wave observations, X-ray astronomy, and particle accelerators. Theory disconnected from observation risks becoming mere mathematical recreation rather than physics. 

Most critically, develop a questioning mindset. Many modified gravity theories make bold claims. Learn to evaluate them critically: Does mathematics hold together consistently? Do the physical predictions make sense? Can they be tested observationally? This skeptical yet-open approach will serve you well, helping distinguish promising ideas from speculative  constructs. 

Finally, seek collaboration with observers and experimentalists. Some of my most fruitful research has emerged from conversations with colleagues who work with real telescopes and detectors. They bring a grounding perspective about what’s actually measurable, which keeps theoretical work honest and relevant. 

Jacobsen: Which shared benchmarks are most urgent for turn ing exotic-gravity claims into decisive, reproducible tests? 

Sakalli: This question strikes at the heart of a crisis facing theoretical cosmology. We have an abundance of modified gravity theories—hundreds, perhaps thousands—each claiming to improve upon Einstein’s general relativity or incorporate quantum effects. Yet we lack systematic standards to distinguish viable theories from mathematical curiosities. Establishing rigorous benchmarks is perhaps the most important task facing our field today. 

The first urgent need is comprehensive waveform libraries. When gravitational waves ripple through spacetime from colliding black holes, the signal encodes information about the underlying gravitational theory. General relativity makes specific predictions about these waveforms. Modified theories predict different signals. We need catalogs of predicted waveforms for all major modified theories, calculated with sufficient precision that we can compare them meaningfully with observations from LIGO, Virgo, and future detectors. These ”shadow libraries” of alternative signals would enable systematic searches through observational data, testing whether nature follows Einstein’s predictions or reveals deviations pointing toward quantum gravity. 

Equally critical is establishing uncertainty budget frameworks. Every theoretical prediction carries errors—from approximations in our calculations, from truncating infinite series, from choosing particular coordinate systems. Yet too often, papers present predictions without honest error estimates. We need standards requiring researchers to quantify theoretical uncertainties alongside observational uncertainties. This transparency would prevent false claims of detecting new physics when observations simply fall within the combined error bars of general relativity plus realistic uncertainty estimates. 

We also need cross-theory comparison protocols—standardized tests that every modified gravity theory must pass before being taken seriously. These should include solar system tests, where we have exquisite precision measurements; binary pulsar systems, which have constrained gravity for decades; gravitational wave observations, our newest probe; and cosmological observations of the universe’s large-scale structure. Any theory failing these established tests should be reconsidered or modified, while theories passing them merit deeper investigation. 

Particularly powerful are null tests—observations designed to distinguish general relativity from entire classes of alternatives without needing to test each theory individually. For instance, if gravitons have mass, they would travel slightly slower than light, causing gravitational waves and light from the same event to arrive at different times. Observing such time delays would rule out massless gravity theories in one shot. Similarly, tests of Lorentz invariance—the principle that physics looks the same regardless of direction or velocity—can constrain whole families of quantum gravity theories. 

Reproducibility standards are equally vital. All computational codes should be publicly available with complete documentation. Independent groups should verify results using different numerical methods. This scientific hygiene prevents errors from propagating through the literature and builds confidence in robust findings. 

For educational materials like textbooks, we need clear labeling distinguishing well-established physics from promising but speculative ideas. Students should learn what we know solidly, what we suspect tentatively, and what remains pure speculation. Mixing these categories without clear boundaries misleads the next generation. 

Jacobsen: How do you enforce cross-paper comparability of assumptions across coauthorship networks? 

Sakalli: Maintaining consistency across collaborative research requires systematic protocols and careful attention to detail. In our research group, we’ve developed several practices that help ensure our papers build coherently on each other rather than contradicting ourselves through subtle inconsistencies. 

We maintain a living standards document that all group members reference. This specifies our notation conventions: Do we use a mostly minus or mostly plus metric signature? How do we define the Riemann curvature tensor’s sign? What units do we adopt? These seemingly minor choices can cause major confusion if they vary between papers. By standardizing them, we ensure that someone comparing results from different papers isn’t misled by notational differences. 

For physical parameters, we document our assumptions explicitly in every paper. When studying black holes surrounded by quintessence dark energy, for instance, we record the assumed equation of state parameter, its range, and why that range is physically motivated based on cosmological observations. This documentation serves multiple purposes: it keeps us honest, helps readers understand our assumptions, and provides a reference when new collaborators join projects. 

Regular group seminars play a crucial role. Graduate students and postdocs present their work in-progress, going through derivations step-by-step. This peer review within the group catches inconsistent approximations before they reach publication. When one student assumes weak field conditions while another works in the strong field regime, group discussions reveal whether their conclusions should match or legitimately differ. 

We also practice computational validation—having different team members independently check numerical results using alternative methods. One person might use Mathematica’s symbolic capabilities, while another writes custom Python code with different algorithms. When both approaches yield consistent results, confidence increases. Discrepancies flag potential errors for investigation. 

Before beginning collaborative projects, we establish explicit agreements about fundamental assumptions, approximation schemes, and the domain of validity we’re targeting. This preemptive alignment prevents the awkward situation where coauthors realize mid-project that they’ve been working under incompatible assumptions. 

Literature alignment is another key practice. We systematically compare our parameter choices with established work in the field. When we need to deviate from standard choices, we document why explicitly in our papers. This transparency helps readers understand whether differences from earlier work represent genuine new insights or simply alternative approaches to the same physics. 

Jacobsen: How does introducing Generalized Uncertainty Principle corrections change emission spectra across standard black holes? 

Sakalli: The Generalized Uncertainty Principle represents one of the most intriguing predictions emerging from various approaches to quantum gravity. Standard quantum mechanics tells us there’s a minimum uncertainty in simultaneously measuring a particle’s position and momentum. The GUP modifies this, introducing a minimum measurable length—roughly the Planck length, about a billion billion times smaller than an atomic nucleus. This modification has profound implications for black hole physics. 

For standard Schwarzschild black holes, Hawking calculated that they emit thermal radiation with a temperature inversely proportional to their mass. Massive black holes are cold; small ones are hot. The GUP modifies this relationship. The Hawking temperature gets corrections that depend on the black hole’s size compared to the Planck length. For astrophysical black holes—even stellar-mass ones—these corrections are unimaginably tiny. But the corrections follow an interesting pattern: they’re suppressed by the ratio of the Planck length squared to the horizon radius squared, which for a solar-mass black hole gives a factor around ten to the minus seventy-eighth power—utterly negligible. 

However, the situation becomes more interesting when we consider spinning black holes and particles of different spins. Scalar particles, fermions, photons, and gravitons all interact differently with the curved spacetime near black holes. Each particle type has characteristic ”greybody factors” describing how likely it is to escape the black hole’s gravitational pull after being created near the horizon. The GUP modifies these factors differently for different particle spins. 

For fermions—particles like electrons with half-integer spin—the GUP corrections depend on the particle’s helicity, its spin direction relative to its motion. Co-rotating fermions, spinning in the same sense as the black hole, experience different GUP corrections than counter-rotating ones. This helicity dependence could, in principle, create asymmetries in the emitted particle abundances. 

For higher-spin particles like photons and gravitons, the effects are even more complex. These particles can extract rotational energy from spinning black holes through a process called su perradiance—think of it as stimulated emission from atoms, but for black holes. The GUP modifies the conditions under which superradiance occurs, potentially changing which frequencies are amplified and how quickly the black hole spins down. 

If we could actually observe these effects, they would manifest as deviations in black hole evaporation rates, altered ratios of different particles in the emission spectrum, modified superradiant instability timescales, and potentially even changes in the black hole’s shadow—the dark silhouette seen by distant observers like the Event Horizon Telescope. 

The sobering reality is that current observational limits constrain the GUP parameter to values that make these effects impossibly small to detect in astrophysical black holes. We would need sensitivity improvements of dozens of orders of magnitude. However, if primordial black holes—tiny ones formed in the early universe—exist and are evaporating today, their much smaller sizes would enhance GUP effects enough to potentially leave detectable signatures in cosmic ray observations. 

Jacobsen: How much can Quasinormal Mode spectroscopy yield universal area quantization across modified-gravity backgrounds? 

Sakalli: When you strike a bell, it rings at characteristic frequencies determined by its shape and com position. Black holes behave similarly. Perturbed by infalling matter or gravitational waves, they ”ring down” by emitting gravitational waves at characteristic frequencies called quasi normal modes. These cosmic bells encode information about the black hole’s properties and, potentially, about the nature of spacetime itself. 

One of the most fascinating conjectures in quantum gravity suggests that black hole area might be quantized—coming in discrete units rather than varying continuously. Shahar Hod originally proposed that highly damped quasinormal modes might reveal this quantization. The idea is beautiful: just as atomic spectra reveal quantum mechanics at microscopic scales, black hole spectra might reveal quantum gravity at macroscopic scales. 

In general relativity, the spacing between highly damped modes approaches a value directly related to the black hole’s temperature. Bekenstein and others showed that if black hole area is quantized, the quantum of area should relate to the asymptotic mode spacing. The connection isn’t exact—there are subtleties about numerical factors—but the possibility that quasinormal modes encode fundamental quantum gravity information is tantalizing. 

Our research into modified gravity theories reveals that this connection is surprisingly robust but not universal. When we add quantum corrections—whether from dilaton fields, quintessence matter surrounding the black hole, or higher-order curvature terms—the quasinormal mode spectrum shifts. Yet in many cases, highly damped modes still show regular spacing patterns that relate to an effective area quantization. 

However, the relationship between mode spacing and area quantization depends on theoretical details: boundary conditions at the horizon, the field content of the theory, and how we define geometric quantities in modified gravity. Not all theories preserve the connection between spectral properties and area quantization. 

The observational challenge is formidable. Current gravitational wave detectors can reliably measure only the first few overtones—the fundamental mode and perhaps the first couple har monics. The asymptotic regime where universal behavior emerges requires observing dozens of overtones. Future detectors like Einstein Telescope and Cosmic Explorer may reach the fifth to seventh overtone for nearby mergers, but extracting highly damped modes remains extremely challenging. 

The most promising approach combines multiple observational probes. Quasinormal mode spectroscopy from gravitational waves provides one window. Black hole shadow observations from radio interferometry provide another. X-ray timing from matter spiraling into black holes offers a third perspective. If quantum gravity corrections affect all these observables consistently, joint analysis could reveal signatures too subtle for any single observation to capture. 

We should be realistic: directly observing Planck-scale quantum effects in astrophysical black holes probably exceeds foreseeable instrumental capabilities. However, quasinormal mode studies may reveal whether area quantization is a universal feature of quantum gravity or specific to certain approaches like loop quantum gravity. They might also detect if quantum gravity involves a characteristic length scale parametrically larger than the Planck length—something not currently ruled out. 

Discussion

Sakallı’s through-line is methodological realism with a contrarian streak: dream big about quantum spacetime, but keep your feet planted in what can be checked. He identifies a genuine structural problem in contemporary gravity research: theoretical supply has outpaced evaluative infrastructure. When hundreds or thousands of modified-gravity frameworks can be written down, novelty becomes cheap; what becomes expensive is decisive discrimination. His proposed remedy is not another “best” theory but a shared testing culture—waveform catalogs for alternatives to general relativity, community expectations for uncertainty quantification, and cross-theory protocols that force models to survive the full obstacle course of solar-system constraints, binary pulsars, gravitational-wave data, and cosmological structure.

That emphasis matters because it reframes “exotic gravity” from a marketplace of clever equations into a cumulative science. In his account, comparability is not an aesthetic preference; it is an anti-chaos device. Standardized sign conventions, explicit parameter ranges, internal seminar scrutiny, and independent computational replication are presented as the difference between a literature that self-corrects and one that merely accumulates. This is a quietly radical point: the next big leap in quantum gravity may arrive not only from new mathematics, but from better scientific hygiene.

On the physics side, Sakallı’s discussion of Generalized Uncertainty Principle corrections and quasinormal-mode spectroscopy illustrates the field’s core tension. The ideas are conceptually sharp—minimum length scales, helicity-dependent emission distortions, superradiance thresholds, spectral signatures that might hint at area quantization—but their detectability is, by his own framing, brutally constrained for ordinary astrophysical black holes. The most interesting possibilities therefore concentrate in special regimes: tiny black holes (including speculative primordial populations), unusually precise ringdown measurements, or joint inference across multiple channels where consistent small deviations might accumulate into something statistically persuasive.

His position on quasinormal modes is especially instructive: the connection between highly damped mode structure and area quantization is “robust but not universal,” which is exactly the kind of statement a maturing field should cultivate. It is neither hype nor dismissal; it is a conditional claim that points to the work that must be done—clarify boundary conditions, define geometric quantities consistently across modified theories, and understand where “universal” behavior actually survives. Observationally, he is frank that the asymptotic regime is hard to reach, but he also gestures toward a sensible strategy: treat gravitational-wave ringdowns, black hole images, and high-energy timing data as complementary constraints rather than rival camps.

The interview’s broader implication is that the “quantum nature of spacetime” is no longer only a metaphysical slogan. It is becoming an empirically pressured research program—but only if the community builds shared benchmarks, publishes reproducible pipelines, and learns to prize null results and constraint-setting as highly as dramatic claims. In that sense, Sakallı’s message is almost humanistic: nature is not obligated to reward our cleverness, but it does reliably reward our honesty.

Methods

The interview was conducted via typed questions—with explicit consent—for review, and curation. This process complied with applicable data protection laws, including the California Consumer Privacy Act (CCPA), Canada’s Personal Information Protection and Electronic Documents Act (PIPEDA), and Europe’s General Data Protection Regulation (GDPR), i.e., recordings if any were stored securely, retained only as needed, and deleted upon request, as well in accordance with Federal Trade Commission (FTC) and Advertising Standards Canada guidelines.

Data Availability

No datasets were generated or analyzed during the current article. All interview content remains the intellectual property of the interviewer and interviewee.

References

This interview was conducted as part of a broader quantum cosmology book project. The re sponses reflect my current research perspective as of October 2025, informed by over 180 publi cations and ongoing collaborations with researchers worldwide. 

Selected References 

General Background and Foundational Works 

Hawking, S.W. (1974). Black hole explosions? Nature, 248(5443), 30-31. Bekenstein, J.D. (1973). Black holes and entropy. Physical Review D, 7(8), 2333. 

Bardeen, J.M., Carter, B., & Hawking, S.W. (1973). The four laws of black hole mechanics. Communications in Mathematical Physics, 31(2), 161-170. 

Modified Gravity and Quantum Corrections 

Sakallı, ˙I., & Sucu, E. (2025). Quantum tunneling and Aschenbach effect in nonlinear Einstein Power-Yang-Mills AdS black holes. Chinese Physics C, 49, 105101. 

Sakallı, ˙I., Sucu, E., & Dengiz, S. (2025). Quantum-Corrected Thermodynamics of Conformal Weyl Gravity Black Holes: GUP Effects and Phase Transitions. arXiv preprint 2508.00203. 

Al-Badawi, A., Ahmed, F., & Sakallı, ˙I. (2025). A Black Hole Solution in Kalb-Ramond Gravity with Quintessence Field: From Geodesic Dynamics to Thermal Criticality. arXiv preprint 2508.16693. 

Sakallı, ˙I., Sucu, E., & Sert, O. (2025). Quantum-corrected thermodynamics and plasma lensing in non-minimally coupled symmetric teleparallel black holes. Physical Review D, 50, 102063. 

Ahmed, F., Al-Badawi, A., & Sakallı, ˙I. (2025). Perturbations and Greybody Factors of AdS Black Holes with a Cloud of Strings Surrounded by Quintessence-like Field in NLED Scenario. arXiv preprint 2510.19862. 

Black Hole Thermodynamics and Phase Transitions 

Gashti, S.N., Sakallı, ˙I., & Pourhassan, B. (2025). Thermodynamic scalar curvature and topo logical classification in accelerating charged AdS black holes under rainbow gravity. Physics of the Dark Universe, 50, 102136. 

Sucu, E., & Sakallı, ˙I. (2025). AdS black holes in Einstein-Kalb-Ramond gravity: Quantum 26 corrections, phase transitions, and orbital dynamics. Nuclear Physics B, 1018, 117081. 

Sakallı, ˙I., Sucu, E., & Dengiz, S. (2025). Weak gravity conjecture in ModMax black holes: weak cosmic censorship and photon sphere analysis. European Physics C, 85, 1144. 

Pourhassan, B., & Sakallı, ˙I. (2025). Transport phenomena and KSS bound in quantum corrected AdS black holes. European Physics C, 85(4), 369. 

Gashti, S.N., Sakallı, ˙I., Pourhassan, B., & Baku, K.J. (2025). Thermodynamic topology, photon spheres, and evidence for weak gravity conjecture in charged black holes with perfect fluid within Rastall theory. Physics Letters B, 869, 139862. 

Quasinormal Modes and Spectroscopy 

Gashti, S.N., Afshar, M.A., Sakallı, ˙I., & Mazandaran, U. (2025). Weak gravity conjecture in ModMax black holes: weak cosmic censorship and photon sphere analysis. arXiv preprint 2504.11939. 

Sakallı, ˙I., & Kanzi, S. (2023). Superradiant (In)stability, Greybody Radiation, and Quasi normal Modes of Rotating Black Holes in Non-Linear Maxwell f(R) Gravity. Symmetry, 15, 873. 

Observational Tests and Gravitational Lensing 

Sucu, E., & Sakallı, ˙I. (2025). Probing Starobinsky-Bel-Robinson gravity: Gravitational lensing, thermodynamics, and orbital dynamics. Nuclear Physics B, 1018, 116982. 

Mangut, M., G¨ursel, H., & Sakallı, ˙I. (2025). Lorentz-symmetry violation in charged black-hole thermodynamics and gravitational lensing: effects of the Kalb-Ramond field. Chinese Physics C, 49, 065106. 

Ahmed, F., Al-Badawi, A., & Sakallı, ˙I. (2025). Geodesics Analysis, Perturbations and Deflec tion Angle of Photon Ray in Finslerian Bardeen-Like Black Hole with a GM Surrounded by a Quintessence Field. Annalen der Physik, e2500087. 

Generalized Uncertainty Principle and Quantum Effects 

Ahmed, F., Al-Badawi, A., & Sakallı, ˙I. (2025). Photon Deflection and Magnification in Kalb Ramond Black Holes with Topological String Configurations. arXiv preprint 2507.22673. 

Ahmed, F., & Sakallı, ˙I. (2025). Exploring geodesics, quantum fields and thermodynamics of Schwarzschild-AdS black hole with a global monopole in non-commutative geometry. Nuclear Physics B, 1017, 116951. 

Wormholes and Exotic Compact Objects 

Ahmed, F., Al-Badawi, A., & Sakallı, ˙I. (2025). Gravitational lensing phenomena of Ellis Bronnikov-Morris-Thorne wormhole with global monopole and cosmic string. Physics Letters B, 864, 139448. 

Ahmed, F., & Sakallı, ˙I. (2025). Dunkl black hole with phantom global monopoles: geodesic analysis, thermodynamics and shadow. European Physics C, 85, 660. 

Information Theory and Holography 

Pourhassan, B., Sakallı, ˙I., et al. (2022). Quantum Thermodynamics of an M2-Corrected Reissner-Nordstr¨om Black Hole. EPL, 144, 29001. 

Sakallı, ˙I., & Kanzi, S. (2022). Topical Review: greybody factors and quasinormal modes for black holes in various theories – fingerprints of invisibles. Turkish Journal of Physics, 46, 51-103. 

Modified Theories and String Theory 

Sucu, E., & Sakallı, ˙I. (2023). GUP-reinforced Hawking radiation in rotating linear dilaton black hole spacetime. Physics Scripta, 98, 105201. 

Event Horizon Telescope and Observational Cosmology 

Event Horizon Telescope Collaboration (2019). First M87 Event Horizon Telescope Results. I. The Shadow of the Supermassive Black Hole. The Astrophysical Journal Letters, 875(1), L1. 

Abbott, B.P., et al. (LIGO Scientific Collaboration and Virgo Collaboration) (2016). Observa tion of Gravitational Waves from a Binary Black Hole Merger. Physical Review Letters, 116(6), 061102. 

Recent Collaborative Works 

Tangphati, T., Sakallı, ˙I., Banerjee, A., & Pradhan, A. (2024). Behaviors of quark stars in the Rainbow Gravity framework. Physical Review D, 46, 101610. 

Banerjee, A., Sakallı, ˙I., Pradhan, A., & Dixit, A. (2024). Properties of interacting quark star in light of Rastall gravity. Classical and Quantum Gravity, 42, 025008. 

Sakallı, ˙I., Banerjee, A., Dayanandan, B., & Pradhan, A. (2025). Quark stars in f(R, T) gravity: mass-to-radius profiles and observational data. Chinese Physics C, 49, 015102. 

Gashti, S.N., Sakallı, ˙I., Pourhassan, B., & Baku, K.J. (2024). Thermodynamic topology and phase space analysis of AdS black holes through non-extensive entropy perspectives. European Physics C, 85, 305. 

Al-Badawi, A., & Sakallı, ˙I. (2025). The Static Charged Black Holes with Weyl Corrections. International Journal of Theoretical Physics, 64, 50. 

Textbooks and Reviews 

Carroll, S.M. (2004). Spacetime and Geometry: An Introduction to General Relativity. Addison Wesley. 

Wald, R.M. (1984). General Relativity. University of Chicago Press. 

Rovelli, C. (2004). Quantum Gravity. Cambridge University Press. 

Kiefer, C. (2012). Quantum Gravity (3rd ed.). Oxford University Press. Ashtekar, A., & Petkov, V. (Eds.) (2014). Springer Handbook of Spacetime. Springer. 

Note: This reference list includes representative works from Prof. Sakallı’s extensive publication record (181+ papers) and foundational works in the field. For a complete bibliography, please consult the INSPIRE-HEP database or Prof. Sakallı’s institutional profile.

Journal & Article Details

Publisher: In-Sight Publishing

Publisher Founding: March 1, 2014

Web Domain: http://www.in-sightpublishing.com

Location: Fort Langley, Township of Langley, British Columbia, Canada

Journal: In-Sight: Interviews

Journal Founding: August 2, 2012

Frequency: Four Times Per Year

Review Status: Non-Peer-Reviewed

Access: Electronic/Digital & Open Access

Fees: None (Free)

Volume Numbering: 13

Issue Numbering: 4

Section: A

Theme Type: Discipline

Theme Premise: Quantum Cosmology

Theme Part: None.

Formal Sub-Theme: None.

Individual Publication Date: December 15, 2025

Issue Publication Date: January 1, 2026

Author(s): Scott Douglas Jacobsen

Word Count: 2,466

Image Credits: İzzet Sakallı

ISSN (International Standard Serial Number): 2369-6885

Acknowledgements

The author acknowledges İzzet Sakallı for her time, expertise, and valuable contributions. Her thoughtful insights and detailed explanations have greatly enhanced the quality and depth of this work, providing a solid foundation for the discussion presented herein.

Author Contributions

S.D.J. conceived the subject matter, conducted the interview, transcribed and edited the conversation, and prepared the manuscript.

Competing Interests

The author declares no competing interests.

License & Copyright

In-Sight Publishing by Scott Douglas Jacobsen is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
© Scott Douglas Jacobsen and In-Sight Publishing 2012–Present.

Unauthorized use or duplication of material without express permission from Scott Douglas Jacobsen is strictly prohibited. Excerpts and links must use full credit to Scott Douglas Jacobsen and In-Sight Publishing with direction to the original content.

Supplementary Information

Below are various citation formats for Quantum Cosmology at the Frontiers of Observation: An Interview with Prof. Dr. İzzet Sakallı (1) (Scott Douglas Jacobsen, December 15, 2025).

American Medical Association (AMA 11th Edition)

Jacobsen SD. Quantum Cosmology at the Frontiers of Observation: An Interview with Prof. Dr. İzzet Sakallı (1). In-Sight: Interviews. 2025;13(4). Published December 15, 2025. http://www.in-sightpublishing.com/quantum-cosmology-frontiers-observation-izzet-sakalli-1 

American Psychological Association (APA 7th Edition)

Jacobsen, S. D. (2025, December 15). Quantum Cosmology at the Frontiers of Observation: An Interview with Prof. Dr. İzzet Sakallı (1). In-Sight: Interviews, 13(4). In-Sight Publishing. http://www.in-sightpublishing.com/quantum-cosmology-frontiers-observation-izzet-sakalli-1 

Brazilian National Standards (ABNT)

JACOBSEN, Scott Douglas. Quantum Cosmology at the Frontiers of Observation: An Interview with Prof. Dr. İzzet Sakallı (1). In-Sight: Interviews, Fort Langley, v. 13, n. 4, 15 dez. 2025. Disponível em: http://www.in-sightpublishing.com/quantum-cosmology-frontiers-observation-izzet-sakalli-1 

Chicago/Turabian, Author-Date (17th Edition)

Jacobsen, Scott Douglas. 2025. “Quantum Cosmology at the Frontiers of Observation: An Interview with Prof. Dr. İzzet Sakallı (1).” In-Sight: Interviews 13 (4). http://www.in-sightpublishing.com/quantum-cosmology-frontiers-observation-izzet-sakalli-1. 

Chicago/Turabian, Notes & Bibliography (17th Edition)

Jacobsen, Scott Douglas. “Quantum Cosmology at the Frontiers of Observation: An Interview with Prof. Dr. İzzet Sakallı (1).” In-Sight: Interviews 13, no. 4 (December 15, 2025). http://www.in-sightpublishing.com/quantum-cosmology-frontiers-observation-izzet-sakalli-1. 

Harvard

Jacobsen, S.D. (2025) ‘Quantum Cosmology at the Frontiers of Observation: An Interview with Prof. Dr. İzzet Sakallı (1)’, In-Sight: Interviews, 13(4), 15 December. Available at: http://www.in-sightpublishing.com/quantum-cosmology-frontiers-observation-izzet-sakalli-1. 

Harvard (Australian)

Jacobsen, SD 2025, ‘Quantum Cosmology at the Frontiers of Observation: An Interview with Prof. Dr. İzzet Sakallı (1)’, In-Sight: Interviews, vol. 13, no. 4, 15 December, viewed 15 December 2025, http://www.in-sightpublishing.com/quantum-cosmology-frontiers-observation-izzet-sakalli-1. 

Modern Language Association (MLA, 9th Edition)

Jacobsen, Scott Douglas. “Quantum Cosmology at the Frontiers of Observation: An Interview with Prof. Dr. İzzet Sakallı (1).” In-Sight: Interviews, vol. 13, no. 4, 2025, http://www.in-sightpublishing.com/quantum-cosmology-frontiers-observation-izzet-sakalli-1. 

Vancouver/ICMJE

Jacobsen SD. Quantum Cosmology at the Frontiers of Observation: An Interview with Prof. Dr. İzzet Sakallı (1) [Internet]. 2025 Dec 15;13(4). Available from: http://www.in-sightpublishing.com/quantum-cosmology-frontiers-observation-izzet-sakalli-1 

Note on Formatting

This document follows an adapted Nature research-article format tailored for an interview. Traditional sections such as Methods, Results, and Discussion are replaced with clearly defined parts: Abstract, Keywords, Introduction, Main Text (Interview), and a concluding Discussion, along with supplementary sections detailing Data Availability, References, and Author Contributions. This structure maintains scholarly rigor while effectively accommodating narrative content.