human: Given a node-centered hypergraph: <hypergraph>, where nodes represent papers and hyperedges represent sets of papers co-cited by a source paper.

Details of the hypergraph:
Center node: "evolution of physical layer communications research in the post 5g era"
  Abstract: The evolving Fifth Generation New Radio (5G-NR) cellular standardization efforts at the Third Generation Partnership Project (3GPP) brings into focus a number of questions on relevant research problems in physical-layer communications for study by both academia and industry. To address this question, we show that the peak download data rates for both WiFi and cellular systems have been scaling exponentially with time over the last twenty five years. While keeping up with the historic cellular trends will be possible in the near-term with a modest bandwidth and hardware complexity expansion, even a reasonable stretching of this road-map into the far future would require significant bandwidth accretion, perhaps possible at the millimeter wave, sub-millimeter wave, or Terahertz (THz) regimes. The consequent increase in focus on systems at higher carrier frequencies necessitates a paradigm shift from the reuse of over-simplified (yet mathematically elegant) models, often inherited from sub-6 GHz systems, to a more holistic view where real measurements guide, motivate and refine the building of relevant but possibly complicated models, solution space(s), and good solutions. To motivate the need for this shift, we illustrate how the traditional abstraction fails to correctly estimate the delay spread of millimeter wave wireless channels and hand blockage losses at higher carrier frequencies. We conclude this paper with a broad set of implications for future research prospects at the physical-layer including key use-cases, possible research policy initiatives, and structural changes needed in telecommunications departments at universities.

Connected through hyperedge HE-1 (induced by source paper "from a human centric perspective what might 6g be"):
  with members:
    - "towards 6g networks use cases and technologies"
    - "capacity and coverage enhancement using long endurance tethered airborne base stations"
    - "enabling smart buildings by indoor visible light communications and machine learning"
    - "a key 6g challenge and opportunity connecting the remaining 4 billions a survey on rural connectivity"
    - "6g the next frontier"
    - "ultrareliable and low latency communication techniques for tactile internet services"
    - "a vision of 6g wireless systems applications trends technologies and open research problems"
    - "six key enablers for machine type communication in 6g"

Question: Please tell me which class the center node belongs to. The 40 classes are: cs.NA(Numerical Analysis), cs.MM(Multimedia), cs.LO(Logic in Computer Science), cs.CY(Computers and Society), cs.CR(Cryptography and Security), cs.DC(Distributed, Parallel, and Cluster Computing), cs.HC(Human-Computer Interaction), cs.CE(Computational Engineering, Finance, and Science), cs.NI(Networking and Internet Architecture), cs.CC(Computational Complexity), cs.AI(Artificial Intelligence), cs.MA(Multiagent Systems), cs.GL(General Literature), cs.NE(Neural and Evolutionary Computing), cs.SC(Symbolic Computation), cs.AR(Hardware Architecture), cs.CV(Computer Vision and Pattern Recognition), cs.GR(Graphics), cs.ET(Emerging Technologies), cs.SY(Systems and Control), cs.CG(Computational Geometry), cs.OH(Other Computer Science), cs.PL(Programming Languages), cs.SE(Software Engineering), cs.LG(Machine Learning), cs.SD(Sound), cs.SI(Social and Information Networks), cs.RO(Robotics), cs.IT(Information Theory), cs.PF(Performance), cs.CL(Computation and Language), cs.IR(Information Retrieval), cs.MS(Mathematical Software), cs.FL(Formal Languages and Automata Theory), cs.DS(Data Structures and Algorithms), cs.OS(Operating Systems), cs.GT(Computer Science and Game Theory), cs.DB(Databases), cs.DL(Digital Libraries), cs.DM(Discrete Mathematics). Directly output the class name.

gpt: cs.IT(Information Theory)